Factors affecting the quality of auditing accounting estimates evidence in big4 auditing companies

Research statement

As Vietnam integrates more into the global economy, business managers face numerous opportunities and challenges To boost competitiveness and attract investment, many resort to tactics that "beautify" financial statements, often under pressure to maximize profits A prevalent method for financial report manipulation among these managers is the use of "accounting estimates."

Accounting estimates, also known as fair values, are critical indicators in financial statements (FS) that have gained prominence with economic growth According to International Standard on Auditing 540 (ISA 540), these estimates involve monetary amounts subject to measurement uncertainty While they enhance the reliability and relevance of FS, they also pose risks due to their inherent uncertainty and the subjective nature of the assessment process, influenced by various factors such as measurement methods and data sources This can lead to material misstatements, as accounting estimates may be manipulated to present a more favorable view of a company's financial position, undermining investor trust, particularly during economic crises Research by Nguyen Thi Le Thanh (2017) highlights that qualified audit opinions often arise from issues related to accounting estimates, with 31% linked to limited audit scope and 24% due to unadjusted material misstatements Thus, while accounting estimates are essential, they frequently contain errors stemming from both intentional and unintentional misjudgments.

The Covid-19 pandemic has severely affected numerous businesses, leading to negative production results, unstable finances, rising bad debts, slow inventory turnover, and a downturn in the stock market Consequently, some companies may feel pressured to present improved financial reports, which can result in intentional omissions or improper accounting estimates.

Financial statements (FS) provide critical insights into a business's operations and financial health, serving not only the enterprise but also stakeholders such as government agencies, investors, and potential partners The accuracy and relevance of FS are increasingly vital in today's economy Over the past 30 years, external auditing has become essential in ensuring the reliability and transparency of FS, fostering investor confidence While this evolution presents growth opportunities for the auditing profession, it also poses significant challenges for auditors, particularly in auditing accounting estimates to maintain high-quality standards.

The research topic "Factors Affecting the Quality of Auditing Accounting Estimates: Evidence in BIG4 Auditing Companies" is essential for understanding how various factors influence the quality of auditing accounting estimates This study aims to identify these factors within independent auditing firms in the BIG4 group and to propose recommendations for enhancing the quality of auditing accounting estimates and, more broadly, the quality of financial statement audits.

Research aims and objectives

1 Nguyen Thi Phuoc (2021) Auditing of accounting estimates during the COVID-19 pandemic Financial journal

The study aims to evaluate how various factors influence the quality of auditing accounting estimates by independent auditing firms within the BIG4 group in Ho Chi Minh City (HCMC) Additionally, it seeks to propose solutions to enhance the quality of these audits.

This study aims to identify and evaluate the factors influencing the quality of auditing accounting estimates conducted by independent auditing firms within the BIG4 group in Ho Chi Minh City.

Secondly, to provide recommendations to improve the quality of auditing accounting estimates, thereby contributing to improving the quality of information on FS.

Research questions

Q1: What factors are currently affecting the quality of auditing accounting estimates in Vietnam and to what extent do they affect it?

To enhance the quality of financial statements (FS), it is essential to address the factors affecting the quality of auditing accounting estimates Implementing rigorous auditing standards and practices can significantly improve the reliability of these estimates Additionally, fostering continuous professional development for auditors will ensure they remain adept at evaluating complex accounting judgments Emphasizing transparency in the estimation process and encouraging open communication between management and auditors can also contribute to more accurate financial reporting Ultimately, these strategies will bolster the overall integrity of financial information, benefiting stakeholders and promoting trust in financial disclosures.

Subject and scope of the research

The research subject of this topic is the auditing of accounting estimates in independent audit firms belonging to the BIG4 group in HCMC b Research scope

The research is conducted from March 2023 to June 2023

The study focuses only on external audit activities and does not investigate other audit activities (state audit, internal audit)

This study exclusively examines the perspectives of auditors and audit assistants regarding accounting estimate auditing within the financial reporting audit processes at independent audit firms in the BIG4 group in Ho Chi Minh City, intentionally excluding insights from other stakeholders such as company Boards of Directors, accountants, and investors.

The study does not address the audit of fair value in the FS Accounting Law

The regulation No 88/2015/QH13, dated November 20, 2015, outlines fair value principles, while the accounting regime for enterprises under Circular 200/2014/TT-BTC, issued by the Ministry of Finance on December 22, 2014, addresses the recognition of asset values and liabilities post-initial recognition concerning fair value Despite these regulations, there remains a lack of specific, official, and unified guidance on the methods and data sources necessary for reliably determining fair value.

Research method

The author employs a mixed research method that integrates qualitative and quantitative approaches Drawing on prior studies in the field, the author builds a theoretical framework and develops a research model, introducing a measurement scale for the relevant variables.

This research seeks to analyze the factors influencing the quality of auditing accounting estimates by synthesizing theoretical foundations and reviewing relevant studies from both domestic and international sources The objective is to uncover commonalities, unique aspects, and research gaps, ultimately proposing a suitable research model The methodology aims to identify the key factors affecting the audit quality of accounting estimates.

The author gathers research samples using various survey tools, including direct email questionnaires and online surveys via Google Docs Following data collection, SPSS software is utilized for analysis, incorporating techniques such as descriptive statistics, frequency analysis, Cronbach's alpha coefficient, exploratory factor analysis (EFA), Pearson correlation analysis, and linear regression analysis This research method aims to assess the impact of factors influencing the quality of auditing accounting estimates, as identified through qualitative methods, ultimately providing recommendations to enhance the quality of these estimates and improve the reliability of financial statements (FS).

Expected contribution

This thesis explores the concept of accounting estimate auditing quality, a relatively underexplored topic in Vietnam, and identifies the factors influencing this quality within independent auditing firms in the BIG4 group in Ho Chi Minh City The research aims to enhance the understanding and documentation of issues related to the quality of accounting estimate auditing.

In terms of practicality, this thesis is a serious scientific research work of the author with some basic contributions as follows:

Re-testing the existing theories on the quality of accounting estimate auditing in the BIG4 environment in HCMC through quantitative research methods

The research findings assist business managers and auditors in recognizing and managing the factors influencing the quality of accounting estimate audits This advancement not only enhances the quality of auditing for accounting estimates but also improves the overall quality of financial statement audits, thereby boosting public confidence in the auditing profession.

Thesis structure

Previous research

 Glover, S M., Taylor, M H., & Wu, Y J (2017) Current practices and challenges in auditing fair value measurements and complex estimates: Implications for auditing standards and the academy Auditing: A Journal of

Glover et al (2017) utilized a mixed-method research approach to investigate auditors' proficiency when supported by valuation experts in auditing accounting estimates The study involved descriptive statistical analysis and surveys from 32 experienced auditors across five audit firms, including three Big 4 firms and two multinational firms, alongside interviews with valuation experts Findings indicated that auditors often struggle due to a lack of experience in preparing accounting estimates, which adversely affects the quality of their audits Notably, 90.6% of auditors reported challenges in evaluating the appropriateness of assumptions used in measurement methods and in reviewing management's accounting estimates.

 Fitzgerald, B C., Wolfe, C J., & Smith, K W (2015) Management’s preference: Can auditors stop it from biasing accounting estimates Working

In their 2015 study, Brian et al investigated how auditors can mitigate management bias in accounting estimates by performing specific audit procedures By surveying experienced auditors from Big 4 firms in the U.S., the research revealed that creating independent estimates or thoroughly assessing audit evidence prior to considering management's estimates can significantly diminish subjective influences The findings indicate that the uncertainty surrounding management's accounting estimates negatively impacts the effectiveness of audit procedures in identifying material misstatements Consequently, the authors recommend that auditors proactively develop independent estimates or evaluate audit evidence to reduce the impact of management's bias on the auditing process.

 Griffith, E E., Hammersley, J S., Kadous, K., & Young, D (2015) Auditor mindsets and audits of complex estimates Journal of Accounting

A study by Griffith et al (2015) examined the challenges faced by auditors in evaluating accounting estimates, particularly complex ones The researchers conducted interviews with experienced auditors and compared their findings to existing auditing standards and PCAOB reporting They identified two primary factors that complicate the auditing process: the emphasis on verifying management's estimation methods—such as assumptions, valuation models, and underlying data—over effective auditing techniques, and the division of knowledge between auditors and specialists, which leaves auditors without essential information needed for thorough evaluations.

Griffith et al (2015) highlighted the significant risks associated with financial statements (FS) due to accounting estimates They stressed the importance for auditors to engage in critical thinking and utilize diverse evidence to assess information effectively A critical mindset enables auditors to identify and connect relevant data, forming a cohesive system to detect unreasonable estimates and develop suitable audit plans Rather than merely gathering evidence, auditors must focus on evaluating its quality The authors underscored that analyzing management's accounting estimates through critical thinking necessitates both experience and expertise in the auditing field.

 Bratten, B., Gaynor, L M., McDaniel, L., Montague, N R., & Sierra, G E

(2013) The audit of fair values and other estimates: The effects of underlying environmental, task, and auditor-specific factors Auditing: A

Journal of Practice & Theory, 32(Supplement 1), 7-44

Bratten et al (2013) identified that professional skepticism and valuation knowledge are crucial individual factors affecting the auditing of accounting estimates As audits grow more complex and the uncertainty surrounding estimates rises, the significance of valuation knowledge continues to increase.

2.1.2 The factors that affect the quality of auditing financial statement

 Calocha, R., & Herwiyanti, E (2020) Factors that affect audit quality Journal of Contemporary Accounting, 35-48

In a quantitative study conducted from March to April 2018, data was collected from 91 auditors in Jakarta's public accounting firms through survey questionnaires The research utilized multiple linear regression analysis via SPSS software to explore five factors affecting audit quality: audit experience, audit professionalism, time budget pressure, audit tenure, and knowledge of detecting errors Findings revealed that knowledge of detecting errors is significantly positively associated with audit quality, while audit professionalism and time budget pressure negatively impacted audit quality Additionally, audit tenure was found to have a non-significant negative effect on audit quality.

 Al Fatlawi, H (2019) Impact Of Audit Factors On Audit Quality Of Investment Audits Funded By ODA Opción: Revista de Ciencias Humanas y Sociales(35), 2942

This quantitative study aimed to analyze the impact of auditors on the quality of audits for investment projects funded by Official Development Assistance (ODA) The research involved a survey of 204 state auditors from the General Department of State Audit and specialized State Audit Offices in Vietnam, conducted between October and December.

In 2017, the author conducted a study utilizing Exploratory Factor Analysis (EFA) and multiple linear regression analysis to investigate five key factors that influence audit quality: auditors' qualifications, professional capacity, experience, professional attitude, and sense of occupational ethics The findings revealed that all factors positively impacted audit quality, with three factors—professional capacity, qualifications, and professional attitude—demonstrating significant influence.

Nguyễn Thị Minh Hiếu (2017) conducted a master's thesis focusing on the factors affecting audit quality in small and medium-sized audit firms in Vietnam The study aimed to identify key influential factors and assess the current state of audit quality within these firms To achieve this, the author utilized a mixed research methodology.

The qualitative method employed in this study involved two key components: first, analyzing secondary information from various sources to establish a theoretical framework for understanding factors that influence audit quality, followed by synthesizing and comparing criteria based on the annual performance results of small and medium-sized audit firms from 2013 to 2015 to evaluate the current state of audit quality in these firms Second, the author conducted surveys using a specially designed questionnaire to gather perceptions and evaluations from auditors and professional staff within these firms.

The quantitative method employed in this study aimed to assess the influence of various factors on audit quality Surveys were distributed through direct and online questionnaires, utilizing Google Docs, while data analysis was executed with statistical techniques supported by SPSS software Key tests, including Cronbach's Alpha analysis, Exploratory Factor Analysis (EFA), correlation analysis, and multiple linear regression analysis, were performed In total, 202 valid questionnaires were collected from 45 small and medium-sized audit firms in Ho Chi Minh City in 2016.

The study identified nine factors affecting audit quality, focusing on small and medium-sized audit firms in Vietnam Key findings revealed that five factors significantly enhance audit quality: auditor competence and expertise, audit fees, quality control measures, auditor experience, and auditor independence The author concluded with practical recommendations aimed at improving the financial statement audit quality in these firms.

 Ngo Sy Trung (2016) The factors affect the quality of FS audit in Vietnam businesses

This study analyzes the factors affecting the quality of financial statement audits in businesses, employing a quantitative research method The research model includes six key factors: the legal environment, business-specific factors, auditor independence, occupational qualifications, the audit firm's quality control system, and others The findings reveal that occupational qualifications are the only significant factor positively impacting the quality of financial statement audits.

Phan Văn Dũng (2015) đã nghiên cứu các yếu tố ảnh hưởng đến chất lượng kiểm toán tại các doanh nghiệp kiểm toán Việt Nam, đặc biệt trong bối cảnh hội nhập quốc tế và nhằm tăng cường năng lực cạnh tranh Luận văn tiến sĩ của ông được thực hiện tại Đại học Kinh tế TP.HCM, đóng góp vào hiểu biết về các yếu tố quyết định đến hiệu quả và chất lượng dịch vụ kiểm toán trong môi trường kinh doanh hiện đại.

This research project aimed to enhance the understanding of audit quality and its impact on the competitiveness of auditing firms in Vietnam, amidst the backdrop of global economic integration Utilizing a mixed research method, the study employed qualitative analysis to assess the current status and influencing factors of audit quality and competitiveness, while the quantitative approach measured the impact of these factors The study identified 13 factors affecting audit quality and 12 factors influencing competitiveness, categorized into auditing firms, auditors, and external factors A survey of 1,000 questionnaires yielded 506 valid responses from various stakeholders in the accounting and auditing sectors The findings revealed that six factors significantly enhance audit quality, including auditor methodology and awareness, external quality control, the legal auditing framework, auditor independence, business strategy, and audit fees Additionally, five factors were found to positively influence competitiveness, such as information technology capability and service quality Notably, six factors of audit quality were identified as significantly boosting the competitiveness of auditing firms in Vietnam.

 DeFond, M., & Zhang, J (2014) A review of archival auditing research Journal of accounting and economics, 58(2-3), 275-326

Research gap

Foreign studies on the factors influencing the quality of audit accounting estimates have been widely researched, yet a clear and comprehensive research model remains undefined Most investigations utilize qualitative methods to explore auditors' perspectives on accounting estimates, focusing on awareness and compliance during the audit process These studies yield insights into critical issues for auditors and offer recommendations to improve auditing quality In contrast, quantitative research identifying factors affecting audit quality is scarce, with existing studies primarily examining general influences on financial audit report quality Noteworthy contributions include works by Calocha and Herwiyanti (2020), Al Fatlawi (2019), DeFond and Zhang (2014), Al-Khaddash et al (2013), Suyono (2012), and Duff (2004) Some research targets specific error-prone financial statement items, such as revenue, as seen in the study by Francis and Gunn (2015) Additionally, these studies highlight the economic, political, cultural, social, and knowledge differences relevant to the Vietnamese context, particularly within independent auditing firms affiliated with the BIG4 in Ho Chi Minh City.

Research on auditing accounting estimates in Vietnam is still in its early stages, primarily focusing on enhancing audit procedures While some quantitative studies have explored factors affecting the quality of financial audit reports—such as those by Nguyen Thi Minh Hieu (2017), Ngo Sy Trung (2016), and Phan Van Dung (2015)—there remains a scarcity of research applying quantitative models specifically to auditing accounting estimates Notable studies in this area include Nguyen Van Quy (2015), Tran Nguyen Bich Hien et al (2020), and Pham Huy Hung (2022) However, these studies often encompass all independent auditing firms across Vietnam This thesis narrows its focus to independent auditing firms within the BIG4 group in Ho Chi Minh City, aiming to accurately define and address the research objectives.

Big-4 auditors primarily serve large companies in complex business sectors, significantly outpacing medium and small firms in market share These large entities often require audits of intricate accounting estimates, which are more complex than those handled by smaller audit firms Despite this, there has been a lack of research on the factors influencing the quality of auditing accounting estimates within major audit firms.

This article explores the factors influencing the quality of auditing accounting estimates within the BIG4 auditing firms, drawing on both domestic and international research to identify existing gaps The author aims to assess the impact of these factors on the quality of external audits and to propose solutions for enhancing the accuracy of auditing accounting estimates and overall financial statement audits.

Research model

The author proposes a research model that identifies key factors influencing the quality of auditing accounting estimates, building on the framework established by Tran Nguyen Bich Hien, Luong Thi Hong Ngan, and Cao Ho (2020) This model specifically highlights the selected factors that impact the auditing quality of accounting estimates.

 Factors related to auditors: Auditor's professional competence, Auditor's professional skepticism

 Factors related to audited entities: Uncertainty of data, assumptions, models, and methods for accounting estimates; Effectiveness of internal control related to accounting estimates

 Factors related to external: Expert support; Legal environment related to accounting estimates

Therefore, the proposed model for factors affecting the audit quality accounting estimates is as follows:

 Dependent factors: Audit quality of accounting estimates

 Uncertainty of data, assumptions, models, and accounting estimate methods

 Effectiveness of internal control related to accounting estimates

 Legal environment related to accounting estimates

Figure 2.1 The proposed research model

Theoretical basis

2.4.1 The concept and nature of accounting estimates

2.4.1.1 The concept of accounting estimates

According to Vietnamese and international auditing standards, accounting estimates represent approximate values for financial reporting items when actual data is unavailable or precise calculation methods are lacking These estimates may manifest as tangible items, including provisions for bad debts, inventory reductions, prepaid expenses, fixed asset depreciation, work-in-progress, deferred revenue, and revenue from incomplete construction contracts Additionally, they can also take the form of intangible items such as warranty expense provisions and accruals.

According to the Public Company Accounting Oversight Board (PCAOB), accounting estimates are components of financial statements that are assessed with a level of uncertainty These complex estimates rely on various assumptions and calculation models, which are becoming more prevalent in financial reporting (Griffith, 2013).

2.4.1.2 The nature of accounting estimates

VSA 540 highlights that the availability and reliability of information for accounting estimates can vary greatly, influencing the uncertainty associated with these estimates This uncertainty subsequently impacts the risk of material misstatements, which may arise from both intentional and unintentional management bias Thus, the nature of accounting estimates is characterized by these varying levels of uncertainty and the potential for bias.

Uncertainty in accounting estimates arises from the imprecise determination and measurement of indicators, relying on various data, models, and estimation methods This variability is influenced by the specific characteristics of each item, the client's business context, and the information available during preparation, ultimately impacting the reliability of these estimates Accounting estimates can pertain to both current and future items, with greater uncertainty associated with projections of future items.

Subjectivity in accounting estimates arises from the practitioner's experience, professional judgment, and ethical principles, with greater complexity leading to increased subjectivity Businesses possess the most relevant internal information and characteristics, which are crucial for accurate accounting estimates However, they may exploit their discretion in data selection and estimation models, potentially skewing financial statements and causing significant distortions, particularly in challenging economic environments.

Despite the inherent uncertainty and subjectivity of accounting estimates, they play a crucial role in improving the transparency and accuracy of financial statements (FS) These estimates are essential for accurately representing the enterprise's value and delivering valuable insights to FS users.

2.4.2 Auditing procedures for accounting estimates

The regulations and guidance on the responsibility of auditors and audited entities regarding accounting estimates and related disclosures during the audit of

FS are specified in VSA 540, in accordance with ISA 540, with specific audit procedures through the following steps:

 Risk assessment procedures and related activities

Auditors must comprehend the audited entity and its environment, including its internal control system, to conduct risk assessment procedures in accordance with auditing standards This understanding is essential for evaluating the risk of material misstatement related to accounting estimates, encompassing both inherent and control risks, as well as detection risk.

- The framework for preparing and presenting FS applicable to accounting estimates, including related disclosures

The Board of Directors (BOD) identifies transactions, events, and circumstances necessitating the recognition or disclosure of accounting estimates in financial statements by conducting interviews to discuss changes that may require new or revised accounting estimates.

The Board of Directors (BOD) plays a crucial role in estimating accounting figures and interpreting data for informed decision-making This process involves utilizing various methods and models for accounting estimates, implementing related controls, and determining whether expert consultation is necessary Additionally, the BOD must assess the assumptions underlying these estimates and identify any changes in accounting methods compared to previous periods Furthermore, evaluating the impact of uncertainty in accounting estimates is essential, along with the strategies employed to address such uncertainties.

The auditor is required to assess the actual outcomes of accounting estimates from prior financial statements and to evaluate the re-performance of those estimates to ensure accurate preparation and presentation of the current financial statements.

 Identifing and assessing material misstatement risks

Accounting estimates inherently involve a significant degree of uncertainty, making them susceptible to material misstatement risks, which can be influenced by both intentional and unintentional biases from the Board of Directors (BOD) To effectively evaluate these risks, auditors must assess the uncertainty surrounding accounting estimates and use their professional judgment to identify any estimates that present a high level of uncertainty, potentially leading to significant misstatement risks.

The auditor must assess the significant risk of misstatement to determine if the Board of Directors (BOD) has properly applied the regulatory framework for preparing and presenting financial statements This includes evaluating the appropriateness and consistency of accounting estimate methods, as well as identifying any changes in accounting estimates or methods that reflect the actual circumstances between the previous period and the current situation.

To address the evaluated risk of material misstatement, the auditor must take the following measures, including the content of accounting estimates such as:

- Verify events occurring up to the date of the audit report

Ensure the BOD's method for accounting estimates is verified, along with the underlying data This includes assessing measurement methods and assumptions that are suitable for the actual circumstances and align with the objectives of the framework for preparing and presenting financial statements.

- Verify the effectiveness of internal controls over the method of accounting estimate made by the BOD with appropriate substantive procedures

- Establish an estimation value to evaluate the estimate made by the BOD

In addition, the auditor must consider whether there is a need for specialized skills or knowledge of one or more aspects of accounting estimates to gather appropriate audit evidence

 Performing further substantive procedure to address the material misstatement risks

When assessing accounting estimates with a risk of material misstatement, auditors must go beyond basic tests and evaluate the Board of Directors' (BOD) consideration of alternative assumptions, the rationale for their choices, and how they manage uncertainty It is essential to determine the reasonableness of the critical assumptions used by the BOD and to understand their plans and capacity for implementing specific actions.

If the auditor suspects that the Board of Directors has inadequately assessed the impact of uncertainty in accounting estimates, which could lead to a significant risk of material misstatement, they are required to create an estimation value to assess the reasonableness of the accounting estimate.

Research process

From March to June 2023, a study was conducted by the author focusing on the BIG4 independent audit firms in Ho Chi Minh City The research aimed to assess the impact of various factors on the quality of auditing accounting estimates within these firms.

The research process involved the following steps:

The author has identified an urgent research problem and existing gaps by analyzing the current situation and previous studies This synthesis of earlier research has led to the identification of key factors and the proposal of a comprehensive research model, as outlined in Chapter 1.

 Synthesized the theoretical basis as a foundation for the research (as already done in Chapter 2)

 Built the research scale and designed the questionnaire and conducted a preliminary expert survey to gather expert opinions on the scale and observed variables in the model

 After conducting the expert survey, the author conducted an official survey using online survey tools with a questionnaire

 Collected the survey data and entered it into SPSS 20.0 software

 Conducted statistical analysis methods such as frequency analysis, reliability and validity assessment of the scale, correlation and regression analysis, and hypothesis testing to evaluate the model

 Concluded the research results and made recommendations accordingly

Research hypothesis

Based on theory, previous studies, and standard content, the author puts forward hypotheses to test the factors influencing the quality of audit estimates as follows:

Auditing accounting estimates necessitates auditors to employ specialized skills and professional judgment beyond basic accounting and auditing knowledge, including expertise in financial analysis, economics, management, and statistics (Martin et al., 2006).

Lack of experience in valuation significantly challenges auditors, as highlighted by Griffith et al (2015) To meet current auditing standards and make informed professional judgments regarding accounting estimates, auditors must possess fundamental knowledge of economic and financial modeling The increasing complexity of accounting estimates related to financial instruments necessitates the use of advanced valuation techniques This lack of experience often forces auditors to depend on valuation experts, as noted by Bratten et al (2013) and Griffith et al (2015) Furthermore, auditors struggle to grasp key risk factors and assumptions within these models due to their limited understanding, which Glover et al (2017) identify as a critical factor impacting the quality of auditing accounting estimates.

A study conducted by Hoang Thi Mai Khanh in 2013 reveals that 60% of auditors in Vietnam acknowledge the limitations they face regarding experience and professional judgment when auditing accounting estimates.

Hypothesis H1: The audit professional competence affects the audit quality of accounting estimates

When auditing accounting estimates, auditors can assess their reasonableness but cannot guarantee their accuracy This necessitates a professional skepticism when evaluating estimates provided by the Board of Directors and conducting relevant audit procedures Given that accounting estimates often rely on subjective data and models, along with uncertain evidence, auditors must maintain a heightened level of professional skepticism throughout the process.

PCAOB investigative reports have identified auditor personality traits, particularly a lack of professional skepticism, as a significant factor impacting audit quality, especially in the context of fair value and accounting estimates (Bratten et al., 2013) Research by Griffith et al (2015) indicates that auditors frequently do not apply adequate professional skepticism when evaluating management's accounting estimates, sometimes opting to rely solely on management's data and assumptions Cannon et al (2017) stress the necessity of professional skepticism in auditing uncertain fair value estimates to minimize errors However, the authors argue that the more pressing issue for auditors is not the absence of skepticism, but rather the challenge of providing affirmative assurance in situations that only warrant negative assurance.

In studies on accounting estimate auditing in Vietnam, Nguyen Van Quy

(2015) and Hoang Thi Mai Khanh (2013) also emphasize the need for auditors to have appropriate levels of professional skepticism when auditing accounting estimates in order to enhance audit quality

Hypothesis H2: The professional skepticism of auditors the audit quality of accounting estimates

The data and models utilized by the Board of Directors (BOD) in accounting estimates are a primary concern for auditors, presenting significant challenges in the auditing process (Nguyen Van Quy, 2015).

Accounting estimates are characterized by the subjectivity of their inputs and the potential inaccuracy of their outputs Auditing these estimates becomes challenging, particularly when they involve subjective data and unique industry characteristics, forcing auditors to assess the client's judgment (Christoffer et al., 2014).

Hypothesis H3: The uncertainty of data, assumptions, models, and accounting estimation methods affects the audit quality of accounting estimates

Auditors must assess the internal control system to evaluate the effectiveness of control procedures designed to identify, prevent, and rectify errors in accounting estimates This process involves reviewing and approving these estimates or delegating authority for their management.

Research indicates that auditors frequently conduct minimal testing of internal controls when auditing accounting estimates, although the necessity of such testing varies by client and specific item Similar findings by Glover et al (2017) reveal that auditors often do not depend on a company's internal controls during these audits The prevailing view is that the subjectivity and uncertainties in assumptions render internal controls ineffective in mitigating risks and lacking reliable third-party evidence Nonetheless, many interviewees emphasized that auditors should consider the effectiveness of internal controls when assessing the reliability of accounting estimates, as companies with stronger internal controls tend to provide more reliable estimates.

Hypothesis H4: The effectiveness of internal control related to accounting estimates affects the audit quality of accounting estimates

Auditors often rely on experts when auditing complex accounting estimates, such as fair value estimates and financial instruments (Bratten et al., 2013; Griffith et al., 2015) However, they frequently accept the results provided by these experts without independently assessing their reasonableness (Griffith et al., 2015) Additionally, Glover et al (2017) highlight the challenges auditors face in utilizing third-party services, particularly in gathering data and evidence to support underlying assumptions and models.

Hypothesis H5: The support from experts affects the audit quality of accounting estimates

In their 2013 study, authors Hoang Thi Mai Khanh and Phan Cao Huyen emphasized the need to enhance auditing procedures for accounting estimates, while Mai Ngoc Anh highlighted the importance of clearly defined legal documents governing these estimates They argued that accounting and auditing standards should align with international regulations, yet be tailored to Vietnam's socio-economic context The authors concluded that the lack of uniformity in legal documents concerning accounting estimates and taxation creates confusion and challenges for practitioners.

Therefore, the legal environment is one of the important factors affecting the quality of audit of accounting estimates that the author includes in the research model

Hypothesis H6: The legal environment related to accounting estimates affects the audit quality of accounting estimates

The hypotheses and their impact on the quality of audit of accounting estimates, including six hypotheses H1, H2, H3, H4, H5, and H6, are presented in Table 3.1 Research hypotheses

Hypo thesis Relationship Cohe sion Source

The audit professional competence affects the quality of auditing accounting estimation

Calocha, R., & Herwiyanti, E (2020); Nguyen Thi Minh Hieu (2017); Ngo Sy Trung (2016); Francis, J R (2015); Al- Khaddash, H., Al Nawas, R., & Ramadan, A (2013)

The professional skepticism of auditors affects the quality of auditing accounting estimation

The uncertainty of data, assumptions, models, and accounting estimation methods affects the quality of auditing accounting estimation

(-) Tran Nguyen Bich Hien et al

H4 The effectiveness of internal controls related to accounting

Van Quy (2015) estimation affects the quality of auditing accounting estimation

The support from experts affects the quality of auditing accounting estimation

(+) Glover et al (2017); Griffith et al (2015)

The legal environment related to accounting estimation affects the quality of auditing accounting estimation

This study will employ quantitative statistical methods to test research hypotheses, aiming to identify and evaluate the factors influencing the quality of accounting estimation auditing and their respective impacts.

Scale formulation

The scale used is the 5-point Likert scale with levels (1) Strongly disagree;

The author identified key factors influencing the quality of audit estimates, as discussed in Chapter 2 By leveraging insights from prior research, a scale for each factor was developed These factors and scales underwent evaluation by experts in the auditing field prior to their finalization and presentation.

 Dependent factor: Audit quality of accounting estimates

The evaluation of audit estimate quality was conducted using a scale derived from theories discussed in Chapter 2, grounded in the definitions of audit quality by DeAngelo (1981), Beatty (1989), and Duff (2004) This scale incorporates diverse perspectives from key stakeholders, including clients, financial statement users, and audited firms, as outlined in VSA 220 The detailed scale is illustrated in Table 3.2.

Table 3.2 The scale of the dependent factor – Audit quality of accounting estimates

The ability to detect and report material errors related to accounting estimates in the

The audited entity and the auditor comply with regulations and professional standards related to accounting estimates

VSA 220, ISA 220, Phan Van Dung (2016)

FS users are satisfied with the honesty and reasonableness of the audit results of the accounting estimates presented in the FS

Tran Van Quy (2015); Tran Nguyen Bich Hien et al (2020)

The satisfaction of the audited entity regarding the contribution and benefits they receive through the audit results of the accounting estimates

Tran Nguyen Bich Hien et al (2020)

The audit report is prepared and issued within the time frame stipulated in the audit contract, and the audit service fees are reasonable

 Independent factors: There are 6 independent factors used in the model as follows:

(1) Scale of audit professional competence

Auditors are required to adhere to relevant auditing standards as outlined in VSA 200, necessitating a comprehensive understanding of the provisions, content, and application guidelines of each standard to effectively meet their objectives Essential skills for auditors include professional judgment, financial acumen, management expertise, and market analysis, alongside a solid foundation in auditing and accounting principles (Martin et al., 2006) Additionally, auditors must possess knowledge and experience in basic valuation to accurately evaluate the evidence provided by the Board of Directors (Martin et al., 2006; Griffith et al., 2015) Research by Francis et al (2015) indicates that auditors with specialized expertise deliver more precise analyses, thereby enhancing the quality of auditing accounting estimates The specifics of this expertise are detailed in Table 3.3.

Table 3.3 The scale of the independent factor - Audit professional competence

A skeptical professional attitude enables auditors to comprehensively assess the characteristics of a business, including its input data, assumptions, and relevant evidence (Cannon et al., 2017; Christoffer et al., 2014; Griffith et al., 2015).

The knowledge of regulations and standards related to accounting estimates helps auditors perform their job better, thereby improving the quality of auditing accounting estimates

Auditors must possess a strong understanding of valuation to effectively evaluate the models, assumptions, and methods employed by management in their accounting estimates This knowledge enables auditors to identify and assess the risks associated with material misstatements in these estimates, ultimately enhancing the overall quality of the auditing process.

Martin et al (2006); Griffith et al (2014)

Auditors with specialized knowledge of the client's specific business sectors can also enhance the quality of auditing accounting estimates

To enhance the quality of auditing accounting estimates, auditors must receive training in financial analysis, economics, management, statistics, and other disciplines beyond traditional accounting and auditing knowledge.

Martin et al (2006) have an appropriate skeptical professional attitude to examine management bias (Aghazadeh et al., 2015) The specific scale is presented in Table 3.4

Table 3.4 The scale of the independent factor - Professional skepticism

(3) Scale of uncertainty of data, assumptions, models, and accounting estimate methods

Auditors face significant challenges due to the limited availability of input data for accounting estimates, making it difficult to conduct independent evaluations This lack of access hinders their ability to verify the accuracy of the accounting estimate data (Hoang Thi Mai Khanh, 2013).

(2017), third parties are unwilling to provide necessary data for auditors to evaluate 42.4% of auditors believe that the uncertainty of future events in assumptions

Auditors must maintain a strong level of professional skepticism when assessing data, models, and methodologies This critical approach enables them to engage in meaningful discussions with management regarding the reasonableness of accounting estimates, ultimately improving the overall quality of the audit process.

Cannon et al (2014); Christoffer et al (2014); Griffith et al (2015)

Auditors need to have an appropriate professional skepticism to perform auditing procedures for accounting estimates to improve the quality of auditing accounting estimates

Tran Van Quy (2015); Tran Nguyen Bich Hien et al (2020)

Auditors need to have an appropriate professional skepticism to detect indicators of intentional or unintentional bias by management in accounting estimates

Aghazadeh et al (2015) highlight the challenges auditors face in evaluating accounting estimates, a sentiment echoed by Glover et al (2017), who found that 90.6% of auditors struggle with assessing the validity of management's assumptions Furthermore, the reliance on unobservable input data significantly undermines the reliability of the information utilized, ultimately impacting the quality of auditing accounting estimates as outlined in VSA 540 For detailed findings, refer to Table 3.5.

Table 3.5 The scale of the independent factor - Uncertainty of data, assumptions, models, and accounting estimate methods

(4) Scale of effectiveness of internal control related to accounting estimates

Effective internal control over accounting estimates involves the Board of Directors' review and approval, alongside a clear delegation of authority to mitigate misstatements (Christofffer et al., 2014; VSA 540) This robust framework minimizes reliance on insufficient evidence, ensuring auditors can gather adequate support for their assessments.

The input data for accounting estimates are not readily available for auditors to independently develop their own estimates to evaluate those of the BOD

Christoffer et al (2014); VSA 540; Hoang Thi Mai Khanh (2013)

Accounting estimates often rely on input data that can be difficult to measure and tied to uncertain future events This inherent uncertainty presents significant challenges for auditors when conducting audit procedures related to these estimates.

Cannon et al (2014); Tran Nguyen Bich Hien et al (2020)

The input data for accounting estimates is closely tied to complex methods and assumptions, requiring auditors to exercise high professional judgment when auditing accounting estimates

The data and model of accounting estimates depend on the specific industry and business environment of the company, which the auditor may lack experience and knowledge

Nguyen Van Quy (2015); Tran Nguyen Bich Hien et al (2020)

The input data and model have a high degree of uncertainty and subjectivity due to intentional or unintentional biases from the

Nguyen Van Quy (2015); Tran Nguyen Bich Hien et al (2020) provide complete documentation The specific scale is presented in Table 3.6

Table 3.6 The scale of the independent factor - Internal control related to accounting estimates

(5) Scale of support from experts

Experts leverage their knowledge and extensive databases to guide businesses in developing accounting estimates, while also assisting auditors in evaluating the reasonableness of these estimates This collaboration enhances the objectivity and reliability of audit evidence, ultimately strengthening the auditing process.

Auditors may face limitations in their expertise when addressing issues beyond the accounting realm, necessitating the involvement of specialists (VSA 540) These experts leverage their professional knowledge and data resources to guide businesses in formulating accounting estimates and assist auditors in evaluating the reasonableness of these estimates (Griffith et al., 2015) This collaboration ultimately enhances the objectivity and reliability of the audit evidence (Cannon et al.).

2017) The specific scale is presented in Table 3.7

Effective internal control over accounting estimates involves clear oversight, approval, and delegation of authority by the BOD to reduce errors and fraud in accounting estimates

Effective internal control helps auditors gather evidence and provide complete documentation of data sources

Effective internal control increases the persuasiveness and reliability of evidence in accounting estimates

Table 3.7 The scale of the independent factor - Support from experts

(6) Scale of legal environment related to accounting estimates

Selecting appropriate treatments for uncertain accounting estimates requires auditors to apply professional judgment, necessitating clear and specific legal regulations It is essential to update accounting and auditing standards related to these estimates to align with international regulations while also adapting them to the Vietnamese economic and social context Additionally, consistency in legal documents concerning tax and accounting estimates is crucial.

Table 3.8 The scale of the independent factor - Legal environment related to

Expert support, combined with specialized knowledge and accessible data sources, enables businesses and auditors to conduct audits of accounting estimates more effectively This collaboration enhances the overall quality of the audit process for accounting estimates.

Survey questionaire

The author developed a survey questionnaire for quantitative research, tailored to align with the designed scale for each factor This questionnaire was refined through expert feedback to accurately reflect accounting estimates and the real-world context in Vietnam, encompassing several key sections.

Table 3.9 Structure of the official survey questionnaire

Likert scale Part 1: General and descriptive information

Part 2: Factors affecting the audit quality of accounting estimates

3 Effectiveness of internal control related to accounting estimates 5 5 points

4 Uncertainty of data, assumptions, models, and accounting estimate methods 3 5 points

6 Legal environment related to accounting estimates 4 5 points

Part 3: Audit quality of accounting estimates 5 5 points

Sample and sampling method

The formal quantitative study employs convenience sampling as its method The necessary sample size is influenced by factors such as the chosen processing method, including regression and exploratory factor analysis (EFA), as well as the required reliability Researchers frequently utilize empirical formulas to ascertain the appropriate sample size for each processing method (Nguyen Dinh Tho, 2013) In the case of EFA, the sample size is typically based on a minimum requirement, which is determined by the number of measurement variables involved in the analysis, as noted by Hair et al.

According to Nguyen Dinh Tho (2013), the minimum sample size for conducting Exploratory Factor Analysis (EFA) should be 50, with a preference for 100, and a recommended observation to measurement variable ratio of 5:1, ideally 10:1 or higher In this study, with 27 observed variables, the minimum sample size required is calculated to be 135 (27 x 5) To ensure an adequate sample size for EFA and linear regression analysis, the author distributed 259 survey questionnaires and collected 260 responses, of which 259 were valid.

Data analysis

Statistical analysis techniques determine the relationships and level of influence of factors affecting the quality of accounting estimates Specifically:

 Collect survey data, consolidate and encode them into the statistical software SPSS 20.0

 Use frequency statistics to calculate the mean and standard deviation of each observed variable

 Evaluate the reliability of the measurement scale using Cronbach's alpha coefficient

Exploratory factor analysis (EFA) is employed to assess two key values of the measurement scale: convergence value and discriminant value This technique effectively reduces numerous observed variables into a few meaningful factor groups while retaining the majority of the original information Researchers commonly agree on specific conditions necessary for conducting EFA.

 The Kaiser Meyer Olkin (KMO) index is a measure that assesses the suitability of factor analysis, which should fall within the range of 0.5 <

 The Bartlett test is statistically significant (Sig < 0.05)

In this research, a factor loading coefficient, or factor weight, greater than 0.5 is deemed significant, especially with a sample size exceeding 100 Consequently, each variable with a loading factor above 0.5 is considered practically important.

 The total extracted variance > 50% indicates the percentage of variance of the observed variable

 Eigenvalue >=1 represents the portion of the variance explained by each factor

 Correlation analysis: used to examine the linear relationship between variables, including the dependent variable and each independent variable, as well as among independent variables

 Linear regression analysis: after concluding that there is a linear relationship between variables, this relationship can be modeled by a linear regression model

 The R 2 (R-Square) and adjusted R 2 values reflect the extent to which the independent variables explain the dependent variable in the regression model, with values closer to 1 indicating a more meaningful model

 The Sig value of the F-test is used to test the adequacy of the regression model

The Durbin - Watson (DW) statistic is used to test for first-order autocorrelation (correlation of adjacent residuals)

Chapter 3 presented the research process, research methods, scale design, questionnaire construction, and sampling procedures The study was conducted using both qualitative and quantitative research methods In the qualitative research, the author used expert opinions to construct and adjust the scale In the quantitative research, the author employed various data analysis and processing techniques such as Cronbach's Alpha, EFA, etc., to test the scale and the appropriateness of the model using SPSS 20.0 software The results of the study will be presented in detail in Chapter 4.

Description of research samples

4.1.1 Descriptive statistics of the sample characteristics

The online survey conducted via Google Forms garnered 260 responses, of which 259 valid entries were retained after filtering out inappropriate submissions, achieving a 99.6% validity rate These responses were analyzed using SPSS 20.0 software, meeting the necessary sample size for the quantitative study outlined in Chapter 3 A detailed list of survey participants can be found in Appendix 2.

The survey sample composition based on the characteristics of the subjects is as follows:

Table 4.1 Descriptive statistics of the observed sample Characteristic

Ernst & Young Vietnam Co., Ltd 106 40.93

From 01 year to under 05 years 99 38.22

From 05 years to under 10 years 24 9.27

From 10 years to under 15 years 3 1.16

CPA (Certified Public Accountants) 9 3.47 ACCA (Association of Chartered

CPA (Certified Public Accountants), Vietnam Association of Certified Public Accountants by VACPA

ACCA (Association of Chartered Certified Accountants), Vietnam Association of Certified Public Accountants by VACPA

Table 4.1 illustrates the characteristics of the survey samples as follows:

 Gender: The survey participants had a gender distribution imbalance, with females accounting for 64.09% and males accounting for 35.91% of the total

The survey included 259 participants from four independent audit firms within the BIG4 group in Ho Chi Minh City Ernst & Young Vietnam Co., Ltd led with 106 participants, representing 40.93% of the total, followed by KPMG Co., Ltd with 64 participants (24.71%), Deloitte Vietnam Co., Ltd with 49 participants (18.92%), and Price Waterhouse Coopers Vietnam Co., Ltd with 40 participants (15.44%).

The survey revealed that the majority of participants were interns, comprising 51.35% with a total of 133 individuals This was followed by 63 staff/audit associates, making up 24.32%, and 58 individuals in senior positions, accounting for 22.39% Lastly, there were 5 participants in manager/senior manager roles, representing 1.93%.

In a recent survey, 51.35% of respondents reported having less than one year of work experience, while 38.22% had between one and five years Additionally, 9.27% of participants had work experience ranging from five to ten years, and only 3 individuals, accounting for a smaller percentage, had a decade or more of experience.

 Education: All 259 survey participants had a university degree, accounting for 100%

In a recent survey, it was found that a significant majority of participants, 79.15% or 205 individuals, did not hold any professional certifications Among those who did, 3.47% (9 individuals) were Certified Public Accountants (CPA), while 15.83% (41 individuals) held Association of Chartered Certified Accountants (ACCA) certifications Additionally, 0.39% (1 individual) possessed both CPA and Vietnam Association of Certified Public Accountants (VACPA) certifications, and 1.16% (3 individuals) had both ACCA and VACPA certifications.

4.1.2 Descriptive statistics of the measurement scale

The study used a 5-point Likert scale to evaluate the factors influencing the audit quality of accounting estimated of BIG4 independent audit firms in HCMC

The author conducted descriptive statistics for each independent and dependent factor and then analyzed the percentage of opinions from the survey participants

The survey results revealed that all observed variables had mean values exceeding the expected average of 3.0, with no significant differences among the variables within the same construct, indicating a consensus among participants Detailed descriptive statistics of the measurement scale can be found in Appendix 3.

Cronbach‟s Alpha

A measurement scale is deemed effective when the overall Cronbach's Alpha coefficient exceeds 0.6 and the inter-item correlation coefficient surpasses 0.3 Testing revealed that the Cronbach's Alpha coefficients for six independent factors influencing the estimated accounting quality of audit firms, along with one dependent factor representing the estimated audit quality, were calculated accordingly.

The independent factors influencing accounting estimates—such as audit professional competence, professional skepticism, the effectiveness of internal controls, data uncertainty, expert support, and the legal environment—demonstrate reliability with a Cronbach's Alpha coefficient exceeding 0.6 Additionally, the inter-item correlation coefficients for these factors are all greater than 0.3, indicating a strong relationship among them.

The table below presents the summary statistics for each factor group and the whole observed variables that meet the requirements for factor analysis using exploratory factor analysis (EFA):

Table 4.2 Cronbach's Alpha reliability testing result

3 Effectiveness of internal control related to accounting estimates 0.842

4 Uncertainty of data, assumptions, models, and accounting estimate methods 0.805

6 Legal environment related to accounting estimates 0.768

7 Audit quality of accounting estimates 0.859

Source: Author's compilation by SPSS 20.0 software

After conducting the Cronbach's Alpha test, the model selected 6 independent variables and 1 dependent variable, resulting in a total of 27 observed variables that were deemed satisfactory.

Result of exploratory factor analysis (EFA)

The author validated the measurement scale's reliability using the Cronbach's Alpha coefficient and performed exploratory factor analysis (EFA) for both independent and dependent variable groups To ensure robustness, only factors with loading coefficients between 0.5 and 1 and a significance level of less than 0.05 were selected Factors with eigenvalues of 1 or higher were retained, and a total extracted variance of 50% or more indicated an appropriate EFA model The results of the exploratory factor analysis are summarized below.

Table 4.3 KMO and Bartlett's test for the independent factors

Kaiser-Meyer-Olkin Measure of Sampling Adequacy .829

Bartlett's Test of Sphericity Approx Chi-Square 2062.675 df 231

- Testing the suitability of EFA: The KMO coefficient = 0.829 > 0.5, indicating that factor analysis is appropriate for the research dataset

- Testing the correlation among observed variables: The Sig coefficient 0.000, indicating statistically significant correlation among the observed variables within the factor

Table 4.4 Eigenvalues and covariance deviations for independent variables

Initial Eigenvalues Extraction Sums of

Rotation Sums of Squared Loadings Total

- Total extracted variance = 64.69% > 50%, indicating that the EFA model is appropriate, and the 6 factors explain 64.69% of the variation in the observed variables

- The Eigenvalues of all 6 factor groups are > 1

Using the Varimax rotation method, the model identified six independent variable groups with factor loadings exceeding 0.5, confirming the convergence and discriminant validity of the measurement scale These six factor groups effectively represent the estimated audit quality, with the rearranged observed variables showing no significant differences from the initially proposed research model.

Table 4.5 Result of independent factor analysis with principal varimax rotation method

Extraction Method: Principal Component Analysis

Rotation Method: Varimax with Kaiser Normalization

- Group 1 consists of the observed variables: UD1, UD2, UD3, UD4, UD5; named Uncertainty of data, assumptions, models, and accounting estimate methods (abbreviated as UD)

- Group 2 consists of the observed variables: PC1, PC2, PC3, PC4; named

Audit professional competence (abbreviated as PC)

- Group 3 consists of the observed variables: LE1, LE2, LE3, LE4; named

Legal environment related to accounting estimates (abbreviated as LEG)

- Group 4 consists of the observed variables: PS1, PS2, PS3; named

Professional skepticism (abbreviated as PS)

- Group 5 consists of the observed variables: IC1, IC2, IC3; named

Effectiveness of internal control related to accounting estimates (abbreviated as

- Group 6 consists of the observed variables: SE1, SE2, SE3; named Support from experts (abbreviated as SE)

Table 4.6 KMO and Bartlett's test for the dependent factor

Kaiser-Meyer-Olkin Measure of Sampling Adequacy .861

Bartlett's Test of Sphericity Approx Chi-Square 545.457 df 10

- Testing the suitability of EFA: The KMO coefficient = 0.861 > 0.5, indicating that factor analysis is appropriate for the research dataset

- Testing the correlation among observed variables: The Sig coefficient 0.000, indicating statistically significant correlation among the observed variables within the population

Table 4.7 Eigenvalues and covariance deviations for dependent variable

Component Initial Eigenvalues Extraction Sums of Squared

Extraction Method: Principal Component Analysis

- Total extracted variance = 64.297% > 50%, Eigenvalues = 3.215 > 1, satisfying the conditions for conducting EFA analysis

Based on the analysis, the observed variables of the dependent variable are grouped into one group as originally intended, and all variables have factor loadings

> 0.5 Therefore, all observed variables are included in the model.

Pearson correlation Analysis

The linear correlation coefficient r is used to test the correlation between 6 independent variables and the dependent variable of audit quality, the author obtained the following results:

AQ PC PS UD IC SE LEG

** Correlation is significant at the 0.01 level (2-tailed)

** Correlation is significant at the 0.01 level (2-tailed)

The results show the Sig coefficient of the Pearson correlation between the independent variables PC, PS, UD, IC, SE, LEG with the dependent variable AQ all

< 0.05 Thus, there is a linear relationship between these independent variables and the dependent variable In which, the PC variable has the strongest correlation with the AQ variable (r = 0.589).

Linear regression analysis

The multiple linear regression function of the 6 factors related to the quality of audit accounting estimates included in the regression analysis is as follows:

AQ PC PS - UD C SE E + 

In which: AQ: Audit quality of accounting estimates

PC: Audit professional competence PS: Professional skepticism

UD: Uncertainty of data, assumptions, models, and accounting estimate methods

IC: Effectiveness of internal control related to accounting estimates SE: Support from experts

LEG: Legal environment related to accounting estimates β 0 : blocking coefficients β 1 , β 2 , β 3 , β 4 , β 5 , β 6 : the regression coefficients for each factor ε: the residual

4.5.1 Level of explanation and multicollinearity test

Applying multiple regression analysis to the model using the Enter method, the author obtained the following results:

Std Error of the Estimate

1 665 a 442 429 39079 1.066 a Predictors: (Constant), LEG, SE, PC, UD, IC, PS b Dependent Variable: AQ

The author assessed the model's adequacy using the R² and adjusted R² coefficients, revealing an R² of 44.2%, which signifies that the model adequately explains 44.2% of the dataset's variation The adjusted R² was 42.9%, indicating that the six independent variables accounted for 42.9% of the dependent variable's variation, with the remaining variation attributed to external factors and random residuals Furthermore, the Durbin-Watson statistic was 1.066, falling within the acceptable range of 1.0 to 3.0, confirming the absence of first-order autocorrelation in the data.

The author used the F-test in the analysis of variance to test the hypothesis regarding the adequacy of the overall linear regression model, the author obtained the following results:

Model Sum of Squares df Mean

Total 68.999 258 a Dependent Variable: AQ b Predictors: (Constant), LEG, SE, PC, UD, IC, PS

The test yielded an F-statistic of 33.302 with a significance level of 0.000, which is less than 0.05 This indicates that the multiple linear regression model is suitable for the dataset and can be effectively applied.

4.5.3 Analyze the results of the regression model

The author used the Variance Inflation Factor (VIF) to test for multicollinearity, the author obtained the following results:

Table 4.11 Result of dependent variables’ linear regression

Standard ized Coefficie nts t Sig

Error Beta Tolera nce VIF

The VIF values for the independent variables were all less than 2, indicating the absence of multicollinearity

The t-test results revealed that the significance levels for the regression coefficients of the independent variables PC, PS, and IC were less than 0.05, indicating a significant explanatory effect on the dependent variable AQ In contrast, the significance values for the independent variables UD, SE, and LEG were 0.441, 0.218, and 0.648, respectively, all exceeding 0.05, which led to their exclusion from the model.

The author utilized β coefficients to assess the significance of independent variables on the dependent variable AQ A higher β coefficient indicates a stronger influence on AQ The independent variables ranked by their impact on AQ are as follows: PC (0.424), IC (0.179), and PS (0.178), demonstrating that PC has the most substantial effect, followed by IC and PS.

The multiple regression analysis revealed that, after excluding the variables UD, SE, and LEG from the model, the remaining independent variables exhibited positive β coefficients, signifying a positive impact on the dependent variable.

AQ Additionally, these three independent variables had Sig values < 0.05, indicating statistical significance Therefore, out of the six hypotheses proposed in Chapter 3, hypotheses H1, H2, and H4 are accepted

The standardized regression equation for the factors influencing the audit quality of accounting estimates is expressed as follows:

In which: AQ: Audit quality of accounting estimates

PC: Audit professional competence IC: Effectiveness of internal control related to accounting estimates PS: Professional skepticism

The analysis reveals that the audit quality of accounting estimates is significantly impacted by the professional competence of auditors, indicated by the highest coefficient β of 0.424 for the variable PC Additionally, the effectiveness of internal control related to accounting estimates also plays a role, as shown by a coefficient β of 0.179 for the variable IC.

The study reveals that professional skepticism (PS) among auditors has the least effect on the quality of accounting estimates, indicating that while there is no significant difference in the influence of internal controls (IC) and professional skepticism, the latter's impact is notably weaker.

Test the research hypothesis

Based on the regression analysis results, the author conducted hypothesis testing as follows, regarding the hypotheses formulated in Chapter 3:

 Hypothesis H1: Audit professional competence has an impact on the audit quality of accounting estimates

PC has β = 0.424; t = 7.918; Sig = 0.000 < 0.05, so hypothesis H1 is accepted Therefore, audit professional competence is one of the factors that influence the audit quality of accounting estimates

 Hypothesis H2: Professional skepticism has an impact on the audit quality of accounting estimates

PS has β = 0.178; t = 3.218; Sig = 0.001 < 0.05, so hypothesis H2 is accepted Thus, professional skepticism is also one of the factors influencing the audit quality of accounting estimates

 Hypothesis H3: Uncertainty of data, assumptions, models, and accounting estimates has an impact on the audit quality of accounting estimates

UD has β = 0.040; t = 0.772; Sig = 0.441 > 0.05, so hypothesis H3 is rejected Therefore, effectiveness of internal control related to accounting estimates does not have an impact on the audit quality of accounting estimates

 Hypothesis H4: Effectiveness of internal control related to accounting estimates has an impact on the audit quality of accounting estimates

IC has β = 0.179; t = 3.309; Sig = 0.001 < 0.05, so hypothesis H4 is accepted Hence, effectiveness of internal control related to accounting estimates is one of the factors influencing the audit quality of accounting estimates

 Hypothesis H5: Support from experts has an impact on the audit quality of accounting estimates

SE has β = 0.065; t = 1.236; Sig = 0.810 > 0.05, so hypothesis H5 is rejected Thus, support from experts does not have an impact on the audit quality of accounting estimates

 Hypothesis H6: Legal environment related to accounting estimates has an impact on the audit quality of accounting estimates

LEG has β = 0.025; t = 0.457; Sig = 0.648 > 0.05, so hypothesis H6 is rejected Therefore, the legal environment related to accounting estimates does not have an impact on the audit quality of accounting estimates

Table 4.12 Hypothesis testing result Hypo thesis Factor t Sig Conclusion

Uncertainty of data, assumptions, models, and accounting estimates

H4 Effectiveness of internal control related to accounting estimates 179 3.309 001 Accept

H6 Legal environment related to accounting estimates 025 457 648 Reject

Research results and discussion

The study identifies three key factors influencing the audit quality of accounting estimates conducted by BIG4 independent audit firms in Ho Chi Minh City, as revealed through multiple regression analysis These factors include audit professional competence, the effectiveness of internal controls related to accounting estimates, and the presence of professional skepticism.

Then, the study addresses the second research question regarding the degree of impact of each factor on the audit quality of accounting estimates through standardized regression coefficients as follows:

Table 4.13 The impact level of factors affecting audit quality of accouting estimates

Audit professional competence 424 54.26 Ranked 1st

Effectiveness of internal control related to accounting estimates 179 22.91 Ranked 2nd

In the context of BIG4 independent audit firms in HCMC, the influence of various factors on audit quality related to accounting estimates is significant, with professional competence of auditors accounting for 54.26% of the impact Additionally, the effectiveness of internal controls contributes 22.91%, while professional skepticism adds 22.83% Notably, all three variables exhibit a positive correlation with the overall quality of audits conducted.

Audit professional competence shows a positive correlation with the quality of accounting estimates, represented by a regression coefficient of 0.424 This implies that, when other variables are held constant, a one-unit increase in audit professional competence results in a 0.424-unit increase in the quality of accounting estimates.

The effectiveness of internal control concerning accounting estimates shows a regression coefficient of 0.179, highlighting a positive correlation with audit quality in accounting estimates This indicates that, when other variables remain constant, a one-unit increase in the effectiveness of internal control results in a 0.179-unit increase in the quality of audits for accounting estimates.

Professional skepticism demonstrates a positive correlation with the quality of accounting estimates, evidenced by a regression coefficient of 0.178 This indicates that, when other variables are held constant, a one-unit increase in professional skepticism results in a 0.178-unit increase in the audit quality of accounting estimates.

After evaluating the scale's reliability through Cronbach's Alpha, conducting Exploratory Factor Analysis (EFA), Pearson correlation analysis, and multiple regression modeling, the author presents a model identifying key factors that influence the audit quality of accounting estimates for BIG4 independent audit firms in HCMC The model highlights three primary factors, ranked by their impact: Audit professional competence, Effectiveness of internal control related to accounting estimates, and Professional skepticism.

Figure 4.1 Model of factors affecting audit quality of accounting estimates

This research underscores the critical role of audit professional competence in the auditing of financial statements, particularly regarding accounting estimates Statistical analysis reveals that 79.2% of respondents support the variable PC1, with an average score of 3.78, while 82.2% agree with PC2, averaging 3.83 Additionally, the observed variables PC3 and PC4 received 80.3% and 84.6% agreement, with average scores of 3.81 and 3.87, respectively These findings align with prior research conducted by Tran Nguyen Bich Hien et al (2020), Al Fatlawi (2019), Nguyen Thi Minh Hieu (2017), Francis (2015), and Al-Khaddash et al (2013).

The effectiveness of internal control related to accounting estimates significantly influences audit quality, aligning with auditing standards and prior research by Hung (2022) and others Survey results indicate that participants perceive a strong impact from internal control variables IC1, IC2, and IC3, with average scores of 3.82 and 3.84 Notably, 86.1% of respondents agree that robust internal control, particularly concerning the Board of Directors' oversight and clear delegation of authority in preparing and recording accounting estimates, effectively minimizes errors and fraud.

The final factor that impacts the audit quality of accounting estimates is

Professional skepticism plays a crucial role in enhancing audit quality, particularly in the evaluation of accounting estimates According to recent statistics, the variable PS2 demonstrates the most significant influence on audit quality, with an average score of 3.87, followed closely by PS1 at 3.85 and PS3 at 3.83 These findings align with previous research conducted by Hung, P H (2022) and Nguyen Van Quy (2015).

The variables related to data uncertainty, assumptions, models, and accounting estimate methods, along with expert support and the legal environment concerning accounting estimates, were excluded from the regression model due to their failure to meet the significance level criteria.

The analysis of the variable Uncertainty in data, assumptions, models, and accounting estimate methods reveals that it lacks statistical significance This finding contrasts with the research conducted by Tran Nguyen Bich Hien et al (2020), which indicated that auditors displayed a relatively high level of agreement, suggesting that they do not fully concur on the impact of data and model uncertainty on the quality of auditing accounting estimates.

Although previous research by Phan Van Dung (2015) indicated that the legal environment related to accounting estimates affects the quality of auditing accounting estimates, this study has proven the opposite

In Vietnam, the practice of auditors seeking support from experts in auditing accounting estimates is not common This lack of expert involvement contributes to the absence of a statistically significant relationship between expert support and the quality of auditing accounting estimates.

Differences in research findings among authors can largely be attributed to varying economic contexts over time Moreover, discrepancies in sampling techniques and survey methods, along with the diverse capabilities of participants across studies, can contribute to random errors in the results.

The author suggests that variations in research outcomes among different models have led to the exclusion of three independent variables, which, despite being statistically significant in prior studies, do not hold the same relevance in the current proposed research model.

Chapter 4 presented detailed results of the quantitative research method Based on the complete questionnaire, the author conducted a quantitative study with a sample size of 259 The survey respondents were interns, staff/audit associates, seniors, and managers/senior managers from independent auditing firms belonging to the BIG4 group in HCMC Subsequently, based on the satisfactory responses, descriptive statistics analysis of the survey participants was conducted, including descriptive statistics of the measurement scale, reliability testing of the scale using Cronbach's Alpha coefficient, and exploratory factor analysis (EFA) The model was tested using Pearson correlation analysis and multiple regression analysis

Conclusions

Accounting estimates are critical in financial reporting due to their inherent uncertainty and susceptibility to various factors, making them prone to manipulation This manipulation can compromise the integrity of financial reports, significantly impacting stakeholders such as investors, creditors, and regulatory agencies Independent auditing is essential in this context, as it evaluates the financial report and assesses the reasonableness of management's accounting estimates, ensuring the accuracy and reliability of the reported figures.

Recent serious fraud cases have highlighted the critical role of auditors and auditing firms, underscoring the need for enhanced transparency and reliability in financial reporting To improve audit quality, particularly concerning accounting estimates, research identified three key factors: auditor professional competence, professional skepticism, and the effectiveness of internal controls related to accounting estimates Each of these factors positively influences audit quality, with higher levels of auditor competence and appropriate skepticism leading to improved outcomes Furthermore, robust internal controls within auditing entities also play a significant role in enhancing the quality of audits related to accounting estimates.

Implications

In Chapter 4, the author presents research findings that lead to specific recommendations aimed at improving the audit quality of accounting estimates for BIG4 independent auditing firms in Ho Chi Minh City, addressing the identified factors.

 Recruitment process and attracting potential candidates

Large-scale auditing firms, such as the Big Four, are known for their transparent and structured recruitment process, which includes several key steps This process typically involves reviewing resumes, evaluating specialized knowledge through writing assessments, conducting group interviews, and culminating in individual interviews.

Candidates seeking positions in auditing firms must demonstrate authentic capabilities to overcome various challenges However, the recruitment process primarily assesses candidates' knowledge and professional skills through tests, neglecting to evaluate their personalities, essential qualities, and adaptability in real-world situations, all of which are crucial for success in the auditing field.

To improve the recruitment process in auditing firms, it is essential to establish a structured and comprehensive approach that thoroughly screens candidates for their professional qualities, including knowledge, skills, ethics, and attitudes Additionally, implementing further assessments to evaluate personal characteristics and situational handling abilities can help identify candidates who exhibit caution, a strong desire to learn, research skills, resilience, analytical capabilities, and effective time management.

The auditing profession in Vietnam, still in its early stages with over 30 years of development, faces challenges due to a limited pool of qualified human resources and varying quality of degrees from universities This disparity has led to high unemployment rates among graduates To harness the potential of young talent, especially in light of stringent recruitment criteria at BIG4 auditing firms, it is essential for auditing firms in Ho Chi Minh City to proactively engage with educational institutions Establishing recruitment offices within universities and collaborating on the development of practical, up-to-date training programs will better align graduates' skills with industry expectations, enhancing their employability and addressing the sector's workforce needs.

To foster stronger ties with the professional landscape, companies should offer training opportunities through internships, research projects, and graduation topics based on real challenges faced by auditing firms This approach not only enables firms to gather innovative ideas and solutions for their issues but also helps students align their career aspirations and develop essential skills and standards in the auditing profession Ultimately, this initiative facilitates the swift identification of qualified candidates and cultivates a robust talent pool for auditing firms in Ho Chi Minh City.

Despite the abundant human resources at BIG4 auditing firms, the scarcity of high-quality talent necessitates a stronger focus on recruitment To enhance the pool of experienced staff, recruitment strategies should extend beyond Ho Chi Minh City and Vietnam to include neighboring countries Implementing attractive incentives for foreign candidates—such as assistance with transportation, visa processes, accommodation, and insurance—will be crucial in attracting skilled professionals from afar.

 Training process and other benefits:

Accounting estimation requires predicting future values and assessing uncertain events, making it crucial for auditors to grasp these complexities for effective audits The author recommends comprehensive training for auditors that focuses on risk identification, appropriate procedures, and expertise in estimating techniques By enhancing their competence and awareness, auditors will be better prepared to evaluate the reasonableness of accounting estimates.

Large-scale audit firms conduct regular training programs for their employees post-peak season, emphasizing the importance of self-learning in enhancing auditors' knowledge and competence By actively researching topics in accounting, auditing, and clients' industries, auditors can significantly improve the quality of financial statement audits, particularly concerning accounting estimates Therefore, auditors must continuously develop their skills not only in specialized areas but also in economics, finance, analysis, and statistics To support this self-learning journey, audit firms should create conducive environments, such as quiet spaces with specialized resources, encouraging auditors to engage in independent study and problem-solving after peak periods.

The auditing profession often faces high work pressure and time constraints, leading many professionals to leave for other career paths after a few years This creates challenges for audit firms, which must continuously recruit and retrain new talent while maintaining professional competence To combat this brain drain, firms should implement effective employee retention policies, particularly for those with specialization certificates Supporting certified auditors in attending knowledge update courses offered by the Vietnam Association of Certified Public Accountants (VACPA) and encouraging participation in relevant professional training can enhance retention Additionally, firms should consider organizing training programs with reputable experts and developing a comprehensive curriculum that includes accounting, auditing, taxation, and soft skills.

5.2.2 Effectiveness of internal control related to accounting estimates

Research in Chapter 4 identifies the effectiveness of internal controls over accounting estimates as a crucial factor impacting audit quality Unfortunately, auditors frequently prioritize control procedures over thorough testing of these estimates, leading to potential irregularities and fraud To strengthen internal controls and enhance audit quality in this domain, several solutions are proposed.

Implementing a strong internal control system for accounting estimates is crucial for businesses to mitigate significant risks and prevent errors This system not only enhances the accuracy and reliability of accounting estimates but also facilitates the identification of discrepancies To improve this process, it is recommended that businesses establish clear accounting policies and estimation procedures tailored to each type of estimate Additionally, there should be a clear delineation of responsibilities among those involved in the review, execution, and verification of accounting estimates The Board of Directors or senior authorities should oversee the review process, while experienced professionals with a solid understanding of accounting and the industry should execute the estimates Those tasked with reviewing should possess the expertise to detect errors or fraud and maintain independence from the individuals who prepared the estimates.

 For audit firms and auditors

In today's fast-paced technological landscape, the efficiency of information processing and storage is vital for effective auditing Auditors face challenges in gathering evidence to uncover potential data manipulation, making the integration of information technology essential in their work It is crucial for auditors, particularly those in Technology Risk/IT Audit roles at BIG4 firms, to comprehend how technology influences internal controls from the planning phase This understanding is especially relevant for businesses utilizing software for bookkeeping, accounting estimates, and automated financial reporting To mitigate risks associated with software applications, auditors must undertake additional procedures to evaluate the software's impact and the potential IT risks involved.

Professional skepticism is a crucial factor affecting the quality of accounting estimates in audits Vietnamese auditing standards require auditors to uphold a skeptical attitude during both the planning and execution phases of the audit To foster and improve this professional skepticism, a comprehensive, multi-faceted approach is essential.

Audited clients present potential risks that may compromise audit independence and professionalism To mitigate these risks, auditing firms in Ho Chi Minh City must prioritize measures that reduce auditor-client familiarity This can be accomplished by implementing a robust personnel management system that clearly outlines dates, times, and work locations, thereby minimizing personal connections that could lead to conflicts of interest.

Limitations and future research

The study utilized a survey ratio of 5:1, resulting in a sample size of 259 participants, primarily consisting of seniors, audit assistants, and interns from BIG4 independent audit firms in Ho Chi Minh City However, the research did not examine the auditing of accounting estimates related to fair value and neglected several other influential factors.

Future research should assess the impact of various factors on the quality of accounting estimates in audits, incorporating insights from both audited companies and investors for a thorough evaluation Additionally, studies could broaden their scope to include the auditing of fair value accounting estimates, considering the roles of both state auditors and internal auditors.

In Chapter 4, the author presents research findings and offers recommendations to improve the audit quality of accounting estimates for independent auditing firms in Ho Chi Minh City The recommendations emphasize three key factors: the professional competence of auditors, the effectiveness of internal controls concerning accounting estimates, and the importance of professional skepticism Additionally, the author acknowledges the study's limitations and proposes directions for future research.

Aghazadeh, S & (2015) How Management‟s Expressions of Confidence Influence

I don't know!

Managements-Expressions-of-Confidence-Influence-Auditors-Testing.pdf

Al Fatlawi, H (2019) Impact Of Audit Factors On Audit Quality Of Investment

Audits Funded By ODA Opción: Revista de Ciencias Humanas y

Sociales(35), 2942 Retrieved from https://produccioncientificaluz.org/index.php/opcion/article/view/27372/280

Al-Khaddash, H A (2013) Factors affecting the quality of auditing: The case of

Jordanian commercial banks International Journal of Business and Social Science, 4(11)

Ban kỹ thuật Tiêu chuẩn Quốc gia (không ngày tháng) Tiêu chuẩn quốc gia TCVN

ISO 9000:2015 là tiêu chuẩn về hệ thống quản lý chất lượng, bao gồm cơ sở và từ vựng liên quan Tiêu chuẩn này được biên soạn bởi Ban kỹ thuật Tiêu chuẩn Quốc gia TCVN/TC 176 về quản lý chất lượng và đảm bảo chất lượng Đề xuất này đã được Tổng cục Tiêu chuẩn Đo lường Chất lượng trình bày và công bố bởi Bộ Khoa học và Công nghệ.

Beckmerhagen, I A (2004) On the effectiveness of quality management system audits The TQM magazine, 16(1), 14-25 Retrieved from https://www.emerald.com/insight/content/doi/10.1108/09544780410511443/ full/html

Bộ Tài Chính đã ban hành Chuẩn mực kiểm toán Việt Nam số 200 vào năm 2012, quy định mục tiêu tổng thể cho kiểm toán viên và doanh nghiệp kiểm toán khi thực hiện kiểm toán theo chuẩn mực này Thông tư số 214/2012/TT-BTC ngày 06 tháng 12 năm 2012 kèm theo tài liệu này nhằm hướng dẫn và đảm bảo tính nhất quán trong hoạt động kiểm toán tại Việt Nam.

Bộ Tài Chính đã ban hành Chuẩn mực đạo đức nghề nghiệp kế toán kiểm toán theo Thông tư số 70/2015/TT-BTC vào ngày 08 tháng 5 năm 2015 Tài liệu này quy định các tiêu chuẩn đạo đức cần thiết cho nghề kế toán và kiểm toán, nhằm nâng cao chất lượng và uy tín của ngành nghề Để tìm hiểu chi tiết, bạn có thể truy cập vào đường dẫn sau: https://thuvienphapluat.vn/van-ban/Ke-toan-Kiem-toan/Thong-tu-70-2015-TT-BTC-Chuan-muc-dao-duc-nghe-nghiep-ke-toan-kiem-toan-290066.aspx.

Bộ Tài Chính đã ban hành Chuẩn mực kiểm toán Việt Nam số 220 về kiểm soát chất lượng hoạt động kiểm toán báo cáo tài chính, kèm theo Thông tư số 214/2012/TT-BTC ngày 06 tháng 12 năm 2012 Tài liệu này có thể được truy cập tại đường dẫn https://docs.kreston.vn/vbpl/kiem-toan/chuan-muc-kiem-toan/vsa-220/.

The article by Bratten (2013) explores the audit of fair values and estimates, emphasizing the impact of various factors such as the environment, specific tasks, and auditor characteristics It provides insights into how these elements influence the auditing process, contributing to a deeper understanding of fair value assessments in financial reporting This research is published in the "Auditing: A Journal of Practice & Theory" and spans pages 7 to 44 in the 32nd volume, supplement 1.

Calocha, R & (2020) Factors that affect audit quality Journal of Contemporary

Accounting, 35-48 Retrieved from https://journal.uii.ac.id/JCA/article/view/18298

Cannon, N H (2017) Auditing challenging fair value measurements: Evidence from the field The Accounting Review, 92(4), 81-114 Retrieved from http://aaajournals.org/doi/10.2308/accr-51569

Christoffer, A & (2014) Audit of Highly Uncertain Accounting Estimates A

Field-based Study of Auditors‟ Attitudes Towards Proposed Audit Responses in ISA 540 Stockholm School of Economics Retrieved from

"http://arc.hhs.se/download.aspx?MediumId"73

Davidson, R A.,, & Neu, D (1993) A note on the association between audit firm size and audit quality Contemporary accounting research, 9(2), 479-488

Retrieved from https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1911- 3846.1993.tb00893.x

Auditor independence is critical for maintaining the integrity of financial reporting, as discussed by DeAngelo (1981) in his examination of "low balling" practices and disclosure regulations He emphasizes the need for transparency to uphold auditor-objectivity Additionally, DeFond and colleagues (2014) provide a comprehensive review of archival auditing research, highlighting key trends and findings that shape the current understanding of auditing practices Together, these works underscore the importance of regulatory frameworks in fostering reliable financial audits.

Duff, A (2004) Auditqual: Dimensions of audit quality

Francis, J R (2015) Industry accounting complexity and earnings properties: Does auditor industry expertise matter 20(2), 15 Retrieved from https://www uts edu au/sites/default/ /AccDG_Francis% 20Gunn WP

Glover, S M (2017) Current practices and challenges in auditing fair value measurements and complex estimates: Implications for auditing standards and the academy Auditing: A Journal of Practice & Theory, 36(1), 63-84

Retrieved from https://www.researchgate.net/publication/305339580_Current_Practices_and_Challenges_in_Auditing_Fair_Value_Measurements_and_Complex_Estima tes_Implications_for_Auditing_Standards_and_the_Academy

Griffith, E E (2010) Auditing Estimates: A Task Analysis and Propositions for

Griffith, E E (2013) Auditing complex estimates: Understanding the process used and problems encountered Audting: A Journal of Practice & Theory, 31(2),

73-111 Retrieved from https://papers.ssrn.com/sol3/papers.cfm?abstract_id57175

Griffith, E E (2015) Auditor mindsets and audits of complex estimates Journal of

Accounting Research, 53(1), 49-77 Retrieved from https://www.researchgate.net/publication/314589441_Auditor_Mindsets_and _Audits_of_Complex_Estimates

Hair, J A (1998) Multivariate data analysis (l n xuất bản 5th) New Jersey,

Prentice Hall Retrieved from https://www.scirp.org/(S(351jmbntvnsjt1aadkozje))/reference/referencespape rs.aspx?referenceid51631

Hoàng Thị Mai Khánh (2013) trong luận văn thạc sĩ của mình đã nghiên cứu về việc hoàn thiện thủ tục kiểm toán ước tính kế toán trong kiểm toán báo cáo tài chính tại các công ty kiểm toán độc lập vừa và nhỏ ở Việt Nam Nghiên cứu này được thực hiện tại Đại học Kinh tế TP.HCM và có thể được truy cập qua liên kết: https://digital.lib.ueh.edu.vn/viewer/simple_document.php?subfolderQ/32/69/&docQ326973400753587161934565335292243552&bitsidS12062d-0b21-47e6-8230-7ba8e91f52f0&uid2935e3-cf70-4531-89da-.

Hoàng Trọng, & Chu Nguyễn Mộng Ngọc (2008) Phân tích dữ liệu nghiên cứu với SPSS (Tập 1, 2) Trường Đại học Kinh tế TP.HCM NXB Hồng Đức

IAASB (2011) Audit quality: An IAASB Perspective Retrieved from https://www.iaasb.org/publications/audit-quality-iaasb-perspective

IAASB (2014) A framework for audit quality Retrieved from https://www.ifac.org/_flysystem/azure-private/publications/files/A-

Framework-for-Audit-Quality-Key-Elements-that-Create-an-Environment- for-Audit-Quality-2.pdf

The IAASB's 2018 project proposal on "ISA 540 (Revised)" focuses on the auditing of accounting estimates, which includes fair value accounting estimates and their related disclosures This proposal aims to enhance the clarity and effectiveness of auditing practices in relation to accounting estimates It emphasizes the importance of accurate disclosures to ensure transparency and reliability in financial reporting.

Janvrin, D (2008) To what extent does internal control effectiveness increase the value of internal evidence? Managerial Auditing Journal, 23(3), 262-282

Retrieved from https://www.emerald.com/insight/content/doi/10.1108/02686900810857712/ full/html?skipTracking=true

Tôi không biết!

Martin, R D (2006) Auditing fair value measurements: A synthesis of relevant research Accounting Horizons, 20(3), 287-303 Retrieved from https://www.researchgate.net/publication/247874757_Auditing_Fair_Value_ Measurements_A_Synthesis_of_Relevant_Research

Ngo Sy Trung (2016) The factors affect the quality of financial statements audit in

Vietnam businesses Asian Social Science, 12(1), 172-181 Retrieved fromhttps://www.ccsenet.org/journal/index.php/ass/article/view/52572

Nguyễn Đình Thọ (2013) Giáo trình phương pháp nghiên cứu khoa học trong kinh doanh

Nguyễn Thị Lê Thanh (2017) đã nghiên cứu về kiểm toán ước tính kế toán trong bối cảnh kiểm toán báo cáo tài chính của các doanh nghiệp tại Việt Nam, do các công ty kiểm toán độc lập thực hiện Luận văn thạc sĩ này cung cấp cái nhìn sâu sắc về quy trình và phương pháp kiểm toán, nhằm nâng cao tính chính xác và đáng tin cậy của báo cáo tài chính Thông tin chi tiết có thể được tìm thấy trên SlideShare.

Nguyễn Thị Minh Hiếu (2017) đã nghiên cứu các nhân tố ảnh hưởng đến chất lượng kiểm toán của doanh nghiệp kiểm toán vừa và nhỏ tại Việt Nam trong luận văn thạc sĩ của mình Nghiên cứu này cung cấp cái nhìn sâu sắc về các yếu tố quyết định đến hiệu quả kiểm toán, góp phần nâng cao chất lượng dịch vụ kiểm toán trong bối cảnh thị trường Việt Nam Tài liệu có thể được truy cập tại địa chỉ: https://digital.lib.ueh.edu.vn/handle/UEH/54420.

Nguyễn Thị Phước (2021) Kiểm toán các ước tính kế toán trong giai đoạn đại dịch

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