Iec tr 62366 2 2016

This tec nical re ort provides MEDIC L DEVICE MA UFA TU ERS with g idan e on how to integrate USABILITY EN INE RIN also cal ed H MA FA TORS EN INE RIN prin iples an US R INT RFA E desig

How SAFETY relates to USABILITY 1 4

The application of USABILITY ENGINEERING is widely recognized as essential to producing

Safe and effective medical devices are crucial for patient care However, past analyses of adverse events, including injuries and fatalities, have revealed that shortcomings in user interface design can result in use errors, leading to serious consequences.

• tubing connector shortcomings and the resulting misconnections of incompatible MEDICAL DEVICES and ACCESSORIES have led to air emboli, poisoning, and asphyxiation;

• confusing menu systems within infusion pumps have led to drug delivery errors, including underdoses, overdoses, and treatment with the wrong drug;

• visual ALARM SIGNAL message ambiguities and the option to override ALARM SIGNALS in dialysis equipment have led clinicians to overlook and misjudge the signs of PATIENT distress

Table 1 – Mapping between the requirements of IEC 62366-1 and the guidance of IEC TR 62366-2

Subcl ause of IEC 62366-1 :201 5 Subclauses of IEC TR 62366-2:201 6

4.1 1 U SABI LITY ENGINEERI NG PROCESS 6 How to implement a USABI LITY ENGI NEERI NG program 6.1 Effective USABILI TY ENGI NEERING programs 6.2 Effective USABILI TY ENGI NEERING projects and plans

6.4 Ensure the necessary resources are available 6.5 R I SK MANAGEMENT as it relates to USABI LITY ENGI NEERI NG

4.1 2 R I SK CONTROL as it relates to USER I NTERFACE design 6.5.2 R I SK CONTROL

4.1 3 Information for SAFETY as it relates to USABI LITY 6.5.3 Information for SAFETY

4.2 U SABI LITY ENGINEERI NG FILE 6.6 U SABI LITY ENGINEERI NG FILE

4.3 Tailoring of the USABI LITY ENGINEERI NG effort 6.7 Tailoring the USABI LITY ENGI NEERI NG effort

5 U SABI LITY ENGINEERI NG PROCESS 7 Overview of the USABI LITY ENGI NEERI NG PROCESS

5.1 Prepare USE SPECIFICATI ON 8 Prepare the USE SPECI FI CATI ON

5.2 Identify USER I NTERFACE characteristics related to

SAFETY and potential USE ERRORS 9 Identify USER I NTERFACE characteristics related to SAFETY and potential USE ERRORS

5.3 Identify known or foreseeable HAZARDS and

HAZARDOUS SITUATI ONS 1 0 Identify known or foreseeable HAZARDS and

5.4 Identify and describe H AZARD - RELATED USE

SCENARI OS 1 1 Identify and describe HAZARD - RELATED USE

5.5 Select the H AZARD - RELATED USE SCENARI OS for

SUMMATI VE EVALUATI ON 1 2 Select the HAZARD - RELATED USE SCENARI OS for

5.6 Establish USER I NTERFACE SPECI FI CATI ON 1 3 Establish USER I NTERFACE SPECI FI CATI ON

To establish a comprehensive User Interface Evaluation plan, it is essential to perform both the design and implementation of the User Interface, followed by formative evaluation This process ensures that the User Interface is effectively tailored to meet user needs while also incorporating necessary training for optimal usability.

1 6 Perform FORMATI VE EVALUATI ONS

5.9 Perform SUMMATI VE EVALUATION of the

USABI LI TY of the USER I NTERFACE 1 7 Perform SUMMATI VE EVALUATI ON

6.5.4 Overall evaluation of RESI DUAL RI SK

Usability engineering is essential for minimizing unacceptable risks associated with medical devices and enhancing patient care by mitigating the chances of harmful use errors through effective user interface design This principle is relevant for medical devices utilized by healthcare professionals, including ventilators, patient monitors, and X-ray machines, as well as those used by laypersons, such as patients and caregivers.

PATIENTS, such as a child or spouse), such as nebulizers, glucose meters, and insulin pen injectors

Annex B lists external resources of reports that MANUFACTURERS can review to identify known problems with USER INTERFACES to avoid when developing a MEDICAL DEVICE of the same or similar type

Medical device safety and usability are closely connected, as features designed to enhance safety, like high and low dosing limits in infusion pump software, also improve usability These dose limits not only protect patients from potential underdoses or overdoses but also provide users with clear guidance on the permissible dosing range This functionality alleviates the cognitive load on users, boosting their confidence when programming the device.

User interface design features aimed at enhancing task speed can improve usability while also mitigating unacceptable risks, particularly in urgent situations like administering therapy for an opioid overdose However, prioritizing speed may lead to the omission of critical confirmation steps, creating new hazardous situations Additionally, a user may inadvertently skip essential procedure steps to expedite the process, increasing the likelihood of use errors and associated risks To prevent these issues, the usability engineering process should be employed effectively.

As such, USABILITY ENGINEERING activities usually serve the dual purpose of reducing MEDICAL

DEVICE unacceptable RISK and enhancing USABILITY A MEDICAL DEVICE ’ S increased appeal is a predictable by-product of the USABILITY ENGINEERING PROCESS

Effective USABILITY ENGINEERING programs 1 6

Effective USABILITY ENGINEERING projects and plans 1 6

To establish a comprehensive User Interface Evaluation plan, it is essential to perform the design, implementation, and formative evaluation of the user interface This process includes not only the creation of the user interface but also the necessary training to ensure effective usage.

1 6 Perform FORMATI VE EVALUATI ONS

5.9 Perform SUMMATI VE EVALUATION of the

USABI LI TY of the USER I NTERFACE 1 7 Perform SUMMATI VE EVALUATI ON

6.5.4 Overall evaluation of RESI DUAL RI SK

Medical device safety and usability are closely connected, as features designed to enhance safety, like high and low dosing limits in an infusion pump's software, also improve usability These dose limits not only protect patients from potential underdoses or overdoses but also provide users with clear guidance on the permissible dosing range This functionality alleviates the cognitive load on users, boosting their confidence when programming the device.

User interface design features aimed at enhancing task speed can improve usability while also mitigating unacceptable risks, particularly in urgent situations like administering therapy to an unconscious patient due to an opioid overdose However, prioritizing speed may inadvertently create hazardous situations if critical confirmation steps are overlooked, leading users to skip essential procedures This increases the likelihood of use errors associated with unacceptable risks To prevent these issues, the usability engineering process should be employed effectively.

5.2 Reasons to invest in USABILITY ENGINEERING

Manufacturers of medical devices increasingly apply usability engineering principles, recognizing the business advantages it offers This approach leads to reduced time to market by preventing delays from late detection of user interface issues and streamlining regulatory reviews with comprehensive submission packages Enhanced sales result from customers viewing these devices as more user-friendly, while intuitive operation simplifies training and reduces the need for customer support Additionally, fewer products are returned as defective, and treatment compliance improves, with patients less likely to abandon their therapies Usability engineering also facilitates better application of existing technology and encourages users to utilize features that may otherwise remain unknown.

6 How to implement a USABILITY ENGINEERING program

To ensure the effective application of Usability Engineering across various product development efforts, it is essential for the manufacturer to establish and maintain a comprehensive Usability Engineering program This program should include clearly defined organizational roles and responsibilities, the establishment of general procedures for key Usability Engineering processes, and the allocation of necessary resources during budgeting cycles to support these activities.

6.2 Effective USABILITY ENGINEERING projects and plans

As part of an effective USABILITY ENGINEERING program, it is highly recommended that the

The manufacturer creates a Usability Engineering project plan for each product development initiative, outlining all related activities throughout the medical device development process, from concept to final design This plan specifies timelines, team member roles and responsibilities, and project-specific costs, ensuring effective integration of usability engineering into the development workflow.

USABILITY ENGINEERING into the MEDICAL DEVICE project development plan and avoids the problems arising from USABILITY ENGINEERING being considered a separate independent

PROCESS Annex D summarizes the USABILITY ENGINEERING project end products U SABILITY ENGINEERING project plans can be integrated into a general MEDICAL DEVICE project plans.

Effective usability engineering projects are essential for demonstrating that the risks associated with use errors in medical devices are minimized to acceptable levels Additionally, these projects contribute to the creation of medical devices that provide a satisfying user experience.

A USABILITY ENGINEERING project can focus on several key areas: updating an existing legacy MEDICAL DEVICE without adding significant new features, developing a line extension MEDICAL DEVICE that shares a similar USER INTERFACE with an existing device while incorporating new features, creating a next generation replacement model that represents a major conceptual shift from its predecessor, or designing an entirely new MEDICAL DEVICE that has no existing counterpart serving the same purpose.

Projects often produce a detailed set of usability engineering records, including a usability engineering file Manufacturers must ensure that usability engineering documentation, like the user interface specification, supports effective usability engineering instead of turning into a burdensome paperwork task that overshadows the user interface design process The essential strategy for success is to adhere to a usability engineering process that meets these needs.

A USABILITY ENGINEERING plan for a project is unique, shaped by the specific USER interactions with the MEDICAL DEVICE It should aim to outline an iterative USER INTERFACE development PROCESS that encompasses research to identify USER GROUPS and USE ENVIRONMENTS, as well as design, prototyping, and USABILITY EVALUATION cycles Additionally, the plan must prioritize the identification and elimination of USE ERRORS to ensure the device is both usable and appealing.

When developing a medical device, it is essential to address all relevant points of user interaction, including hardware, software, user support components, and labeling such as embedded help and user manuals Establish usability goals specifically for commercialization, while planning the necessary design, evaluation, and testing processes Identify the usability engineering methods to be employed and create the corresponding usability engineering records, which form the core of the usability engineering file Additionally, include a schedule outlining the expected progression of usability engineering activities throughout the medical device development project, allowing for design iterations as needed to achieve a successful outcome Finally, prepare submissions for the Authority Having Jurisdiction (AHJ).

Ensure the necessary resources are available and well timed 1 8

R ISK MANAGEMENT as it relates to USABILITY ENGINEERING 1 8

R ISK ANALYSIS 1 8

The MANUFACTURER should integrate USABILITY ENGINEERING and RISK MANAGEMENT efforts The documentation of USE ERROR HAZARD analysis should be shared by the persons responsible for

RISK MANAGEMENT and USABILITY ENGINEERING For example, a shared USE ERROR HAZARD analysis document can be an input to both the RISK MANAGEMENT team and USABILITY ENGINEERING team

Manufacturers must address use errors with the same seriousness as other medical device failures, including mechanical, electrical, and software issues It is crucial to acknowledge that deficiencies in user interface design can result in use errors, potentially causing significant harm According to IEC 62366-1:2015, Table B.2, there are specific examples that illustrate these concerns.

USE ERRORS, which are part of the sequence of events that lead to HAZARDOUS SITUATIONS leading to HARM The MANUFACTURER should consider a wide range of possible USE ERRORS

USE ERRORS are distinct from component failures, as accurately estimating their occurrence probability is often more challenging Due to this complexity, manufacturers should prioritize addressing USE ERRORS in their processes.

SEVERITY of the potential HARM rather than on the RISK derived from the combination of

SEVERITY and USE ERROR probability

When developing a medical device, manufacturers must take into account potential use errors, which include performing incorrect actions (errors of commission) and failing to perform necessary actions (errors of omission).

When designing a medical device, manufacturers must consider various factors that can lead to use errors These include environmental distractions, excessive workload, fatigue, and inattention Additionally, insufficient experience and training with the device, as well as a lack of familiarity with relevant terminology and documentation, can contribute to errors User impairments, such as vision or hearing issues, and the misapplication of experience from other devices can also pose risks Overconfidence in abilities, organizational hierarchy, fast-paced work environments, and task interruptions further complicate safe device usage.

Additional information is contained IEC 62366-1 :201 5, Annex A rationale to 3.21 , regarding the causes of USE ERROR.

R ISK CONTROL 1 9

To minimize use-related risks, it is essential to follow safety principles as outlined in ISO 14971:2007, section 6.2 These principles prioritize the implementation of inherent safety by design, the incorporation of protective measures within the medical device or its manufacturing process, and the provision of safety information.

Inherent SAFETY by design is the first option, because it is most likely to effectively reduce the

RISK or even remove it The best way to prevent a USE ERROR and the possible resulting HARM is to eliminate a HAZARDOUS SITUATION altogether

Another way to design a MEDICAL DEVICE is with built-in protections against USE ERRORS

EXAMPLES Physical guards over a critical control, an interlock preventing accidental control actions, requiring

USERS to confirm critical actions

Protective measures integrated into the medical device or implemented during the manufacturing process serve as a secondary option However, these measures may sometimes fail or depend on human intervention to be effective.

NOTE 1 A person can fail to react for a number of reasons

Protective measures are frequently implemented as a complement to design risk control measures, which alone may not sufficiently lower risk to an acceptable level For detailed examples, refer to IEC 62366-1:2015, Table B.2.

Information for safety is crucial but is often the least effective option due to several factors First, users must have access to the information, which can be challenging if, for example, instructions are lost or training sessions are not conducted Second, users need to be able to learn from the information; even if it is clear and supports correct use, it may not be as effective as design-based risk control measures Lastly, users must be able to recall the safety information when needed.

Safety information is essential for managing risks that may be deemed unacceptable, as well as for those that, while acceptable, could still lead to events that users should be cautioned about.

NOTE 2 The generic term ‘warning’ can refer to one of several specific indications that utilize the signal words danger, warning, caution and notice

Safety information for medical devices includes not only warnings but also instructions for correct usage, which can serve as an effective risk control measure.

Information for SAFETY can also be required by product standards and other sources Additional information is found in 6.5.3

The SAFETY principle in RISK CONTROL for MEDICAL DEVICES emphasizes the importance of addressing design changes outside the USER INTERFACE to minimize USE ERRORS before implementing protective measures within the USER INTERFACE For instance, in a MEDICAL DEVICE where touching a live wire poses a risk, the MANUFACTURER should prioritize SAFETY by design, such as switching from line voltage to battery cells, rather than solely relying on protective measures like a removable hood for the power supply.

Inherent SAFETY (i.e a redesign in the USER INTERFACE) should be applied before introducing protective measures (e.g an ALARM SYSTEM), which again should come before introducing more information for SAFETY

When deciding to implement multiple options, the MANUFACTURER must assess not only the acceptability of the RISK but also whether the option can further mitigate that RISK For instance, an additional warning for an unlikely event may prove ineffective, while a warning for a likely yet acceptable RISK can better address USER needs and should be prioritized for implementation.

Manufacturers must employ usability engineering to evaluate the effectiveness of risk control measures in the user interface, ensuring safety information is compliant with ISO 14971 This process should also identify new risks that may emerge from these implemented measures To assess the adequacy of risk control, various techniques, including heuristic analysis and usability testing, can be utilized to identify potential use errors Additional considerations for heuristic analysis are outlined in Clause E.11.

Information for SAFETY and overall RESIDUAL RISKS weighed against benefit is described in ISO/TR 24971 :201 3, Clause 5 [3]

Overall evaluation of RESIDUAL RISK

Medical device safety and usability are closely connected, as features designed to enhance safety, like high and low dosing limits in an infusion pump's software, also improve usability These dose limits not only protect patients from potential underdoses or overdoses but also provide users with clear guidance on the permissible dosing range This functionality alleviates the cognitive load on users, boosting their confidence when programming the device.

User interface design features aimed at enhancing task speed can improve usability while also mitigating unacceptable risks, particularly in urgent situations like administering therapy for an opioid overdose However, increased speed may lead to hazardous situations if critical confirmation steps are overlooked, as users might skip essential procedures to expedite their actions This can elevate the likelihood of use errors associated with significant risks To prevent these issues, the usability engineering process should be employed effectively.

5.2 Reasons to invest in USABILITY ENGINEERING

Manufacturers are increasingly applying usability engineering principles in the development of medical devices, recognizing the business advantages it offers This approach leads to reduced time to market by preventing delays from late detection of user interface issues and streamlining regulatory reviews with comprehensive submission packages Enhanced sales result from customers viewing these devices as more user-friendly, while intuitive operation simplifies training and reduces the need for customer support Additionally, fewer products are returned as defective, and treatment compliance improves as patients are less likely to abandon their therapies Usability engineering also facilitates better application of existing technology and encourages users to fully utilize available features.

6 How to implement a USABILITY ENGINEERING program

To ensure the effective application of Usability Engineering across various product development efforts, it is essential for the manufacturer to establish and maintain a comprehensive Usability Engineering program This program should include clearly defined organizational roles and responsibilities, the establishment of general procedures for key Usability Engineering processes, and the allocation of necessary resources during budgeting cycles to support these activities.

6.2 Effective USABILITY ENGINEERING projects and plans

As part of an effective USABILITY ENGINEERING program, it is highly recommended that the

The manufacturer creates a Usability Engineering project plan for each product development initiative, outlining all usability-related activities throughout the medical device development process, from concept to final design This plan specifies timelines, team member roles and responsibilities, and project-specific costs, ensuring effective integration of usability engineering into the development workflow.

USABILITY ENGINEERING into the MEDICAL DEVICE project development plan and avoids the problems arising from USABILITY ENGINEERING being considered a separate independent

PROCESS Annex D summarizes the USABILITY ENGINEERING project end products U SABILITY ENGINEERING project plans can be integrated into a general MEDICAL DEVICE project plans.

Effective usability engineering projects are essential for demonstrating that the risks associated with use errors in medical devices are minimized to acceptable levels Additionally, these projects contribute to the creation of medical devices that provide a satisfying user experience.

A USABILITY ENGINEERING project can focus on several key areas: updating an existing legacy MEDICAL DEVICE without adding significant new features, developing a line extension MEDICAL DEVICE that shares a similar USER INTERFACE with an existing device while incorporating new features, creating a next generation replacement model that represents a major conceptual shift from its predecessor, or designing an entirely new MEDICAL DEVICE with no existing counterparts that function similarly to achieve the same purpose.

Projects often produce a detailed set of usability engineering records, forming a usability engineering file Manufacturers must ensure that usability engineering documentation, including the user interface specification, supports effective usability engineering instead of turning into a burdensome paperwork task that overshadows the user interface design process The essential strategy for success is to adhere to a usability engineering process that meets these needs.

A USABILITY ENGINEERING plan for a medical device project is unique, shaped by the specific user interactions involved It should aim to outline an iterative user interface development process that encompasses research to identify user groups and use environments, as well as design, modeling through prototype creation, and usability evaluation cycles Additionally, the plan must prioritize the identification and elimination of use errors to ensure the device is both usable and appealing.

When developing a medical device, it is essential to address all aspects of user interaction, including hardware, software, user support components, and labeling such as embedded help and user manuals Establish usability goals focused on commercialization, rather than safety, and plan for relevant design, evaluation, and testing Identify the usability engineering methods to be employed and create necessary usability engineering records, which form the core of the usability engineering file Additionally, include a schedule outlining the progression of usability engineering activities throughout the medical device development project, allowing for design iterations as needed to achieve a successful design Finally, prepare submissions for the Authority Having Jurisdiction (AHJ).

6.3 Apply an appropriate level of USABILITY ENGINEERING expertise

It is recommended for a MEDICAL DEVICE development team to have available adequate

Usability engineering requires expertise, including the involvement of a usability specialist with relevant training in usability engineering and knowledge of the medical device domain This expertise can be acquired through formal education in usability engineering, along with practical experience in applying the usability engineering process.

Individuals with expertise in usability engineering can be self-taught or have completed specialized courses that focus on essential concepts and best practices for medical device development.

Various professionals can actively engage in Usability Engineering activities, including contributing to project plans, analyzing usability issues, designing or modifying medical device user interfaces, and observing usability test results Key participants include technical writers who create learning tools like user manuals and online help, training course developers and trainers, marketing specialists who understand the distinction between usability engineering and market research, clinicians with a strong user perspective, developers who prototype user interfaces for usability tests, and engineers and designers who apply usability engineering principles in their work or oversee usability efforts within development teams.

6.4 Ensure the necessary resources are available and well timed

A successful USABILITY ENGINEERING project is crucial for the development of MEDICAL DEVICES, as insufficient funding or time can hinder its effectiveness and jeopardize regulatory clearance To ensure timely market launch and achieve desired outcomes, it is essential that these projects receive adequate financial support.

U SABILITY ENGINEERING FILE

MANUFACTURERS should store RECORDS of USABILITY ENGINEERING activities to establish a

The information gathered during the Usability Engineering Process is a crucial resource for various development activities Easily accessible records can significantly benefit the development team Annex D provides a summary of the key end product records generated throughout the Usability Engineering Process.

The RECORDS created by conducting the USABILITY ENGINEERING PROCESS also provide

OBJECTIVE EVIDENCE for the activities required by IEC 62366-1 and are necessary to demonstrate compliance to that standard

Usability engineering records encompass both written documents and multimedia materials, such as photographs and videos, gathered during interactions with potential users These materials are typically collected through user interviews, field observations, or usability tests.

The Usability Engineering Process is closely linked to other processes, such as the Product Realization Process and Risk Management Process, as outlined in ISO 13485 The outcomes of Usability Engineering activities enhance these processes and their records Integrating records from the Usability Engineering Process into related documents can be beneficial; for instance, the User Interface Specification can be included in the overall product specification of the Product Realization Process, while for software, it can be part of the Software Requirements Specification Additionally, the Usability Evaluation Plan can contribute to the verification and validation plan of the Product Realization Process, and analyses of known use problems and foreseeable use errors can be incorporated into the Risk Management File.

Tailoring the USABILITY ENGINEERING effort

Tailoring the USABILITY ENGINEERING project to the specific needs of a MEDICAL DEVICE development is crucial, as some devices carry minimal RISK from USABILITY issues, while others may pose significant dangers if HAZARDS are not proactively identified and managed Consequently, the duration of a USABILITY ENGINEERING project can vary greatly, ranging from just a few weeks to several years, depending on the complexity and risk associated with the device.

Medical devices with complex functions, such as haemodialysis equipment, MRI scanners, or anaesthesia workstations, typically require a more comprehensive usability engineering project In contrast, simpler medical devices like lancing devices, nebulizers, or sphygmomanometers may present higher usability risks, necessitating increased usability engineering efforts to mitigate these risks effectively.

RISKS The probability of occurrence of encountering a HAZARD, which is one component of

RISK, can be very difficult to estimate, especially for a novel MEDICAL DEVICE for which no

Post-production data is accessible, making the severity of potential harm from a medical device a key factor to consider before implementing risk control This should be the primary focus when designing a usability engineering project.

When modifying an existing user interface, a focused usability engineering effort is necessary for the changed elements and their impact on the medical device's usability Unchanged elements may not require additional usability engineering, especially if the modifications do not affect the user interface or the use specification remains the same Additionally, if there are existing usability engineering records from previous standards, such as IEC 62366, this can inform the tailoring process for the modifications.

Accordingly, a MEDICAL DEVICE-specific USABILITY ENGINEERING project might describe activities spanning weeks, months, or even years Initial USER research efforts and subsequent

Usability testing can vary in scale, ranging from fewer than 10 participants to over 50, impacting the resulting user interface design This design may incorporate numerous hardware and software components or just a few Users may depend on extensive accompanying documentation, a straightforward instruction sheet, or their own intuition to navigate the interface effectively.

Usability engineering activities can be customized to include essential components such as background user research and user interface design Background user research determines the necessary extent of research to identify a comprehensive set of user needs, which may vary across different markets User interface design involves multiple iterations to achieve an optimal solution; some projects may reach a satisfactory design after a few iterations, while others, particularly in the development of medical devices, may require numerous iterations to refine concepts into a final design.

For simpler products like a bedpan, the development team may finalize the design after just a few iterations In contrast, more complex products such as a dialysis machine require a more extensive iterative process, involving multiple concepts for each module before arriving at the final design Additionally, the effectiveness of formative evaluations, which are conducted prior to summative evaluations, depends on their quantity, complexity, and the number of participants involved in these tests.

The need to assess multiple design options and resolve persisting USER interaction problems might lead a development team to conduct several FORMATIVE EVALUATIONS of varying focus and formality

EXAMPLE 2 A MANUFACTURER established a project plan calling for at least two FORMATIVE EVALUATI ONS prior to the SUMMATIVE EVALUATI ON during a development PROCESS

EXAMPLE 3 A MANUFACTURER decided not to perform any FORMATI VE EVALUATION because the USER

I NTERFACE had already undergone SUMMATI VE EVALUATI ON , and the only change was to add a new (but very similar) intended USER GROUP

Effective usability engineering recommends conducting at least one formative evaluation before any summative evaluation Summative evaluations vary in quantity and complexity, depending on the number of participants involved A single usability test with one user group may suffice to evaluate all hazard-related use scenarios for intended users, while multiple sessions may be necessary for different user groups with distinct responsibilities related to the medical device, such as installation, clinical use, or maintenance If summative evaluation results reveal that user interface elements need modification to mitigate risks, further summative evaluations can focus on the affected user interactions and interface components Good usability engineering practices take into account the risk and complexity of the user interface to determine the necessity and number of summative evaluations Additional details can be found in Clause 12.

7 Overview of the USABILITY ENGINEERING PROCESS

USABILITY ENGINEERING PROCESS activities should be aligned with other development activities Similar to other kinds of projects, such as those developed to ensure manufacturing quality or

The reliability of medical devices is ensured through a comprehensive usability engineering process, which is typically outlined in a detailed plan This plan may exist as a standalone document or be incorporated into the overall development strategy For further details, refer to section 6.2.

Figure 1 presents a USABILITY ENGINEERING project example, outlining a plan for developing a graphical USER INTERFACE It showcases the application of various methods detailed in this technical report to facilitate USER INTERFACE development To clarify the relationship between these methods and the subsequent Clauses of the report, the relevant clause headings are indicated in each phase Clauses 8 to 18 offer comprehensive guidance for implementing a USABILITY ENGINEERING project.

10 Identify HAZARDS and HAZARDOUS SITUATIONS

11 Identify and describe HAZARD-RELATED USE SCENARIOS

12 Select HAZARD-RELATED USE SCENARIOS for SUMMATIVE EVALUATION

14 Establish USER INTERFACE EVALUATION plan

15 Design and implement the USER INTERFACE

Ite ra tio n X (i f n ee de d) It er at io n 2 It er at io n 3 It er at io n 1

Conduct contextual inquiries Conduct focus group with advisory panel

Conduct TASK analysis incl PCA analysis

Conduct workshop with RISK MANAGEMENT team

Identify, describe, and categorize HAZARD-RELATED USE SCENARIOS

Develop USER INTERFACE design concepts

Refine USER INTERFACE design Implement USER INTERFACE in product

S UMMATIVE EVALUATION: USABILITY TEST Evaluate RESIDUAL RISKS related to USABILITY according to ISO 14971:2007, 6.4

Refine USER INTERFACE design Implement changes in product

Establish USER INTERFACE EVALUATION plan

Review historical internal POST-PRODUCTION information

U SE R re se ar ch A na ly si s D es ig n an d FO R M A TI V E EV A LU A TI O N SU M M A TI V E EV A LU A TI O N

NOTE An explanation of PCA analyses is found in Clause E.1 5

Figure 1 – Example of a USABILITY ENGINEERING project for a graphical USER INTERFACE

The example project is laid out in four phases: a) USER research; b) analysis; c) design and FORMATIVE EVALUATION; and d) SUMMATIVE EVALUATION

The implementation phase in this example is planned to have three iterations However, the example also acknowledges that additional iterations might be necessary in case the

FORMATIVE EVALUATION results from previous iterations are not satisfactory

For comprehensive insights into the methods referenced, please refer to Annex E According to IEC 62366-1:2015, section 4.1.1, the methods, techniques, and sequence of activities may differ across various USER INTERFACE development projects.

Usability engineering projects in the medical device design process can differ significantly in scale and structure They may follow a linear approach with varying degrees of rigor, involve multiple design iterations, and utilize diverse prototyping methods Despite these differences, the primary objective remains the same: to ensure the effective application of usability engineering principles.

Initiate USE SPECIFICATION

The MEDICAL DEVICE USE SPECIFICATION serves as the essential basis for the USER INTERFACE SPECIFICATION It outlines critical elements that are vital for the specification and design of both the MEDICAL DEVICE and its USER INTERFACE These elements help identify known and foreseeable HAZARDS and HAZARDOUS SITUATIONS associated with the USER INTERFACE A thorough understanding of these components is crucial for creating an effective USABILITY EVALUATION plan.

A preliminary USE SPECIFICATION is essential for initiating a USABILITY ENGINEERING research effort, as it gathers the necessary information to plan and conduct USER research activities such as observations, interviews, and surveys At this stage, the USE SPECIFICATION is typically based on existing knowledge rather than insights from USER research, resulting in a high-level overview rather than a detailed record It may even resemble a preliminary draft of the project's objectives.

The intended use of this document includes identifying the user groups targeted for interviews, specifying the use environment to be examined, and outlining the medical indications that require further investigation.

The USE SPECIFICATION is refined over time while more knowledge is gained through USER research While the USER research phase progresses, the level of detail and accuracy of the

The increase in USE SPECIFICATION may lead to the discovery of new USER GROUPS during USER research If identified, these USER GROUPS will be incorporated into the USE SPECIFICATION, potentially initiating further USER research activities.

Analyse the intended USERS , anticipated USER TASKS and intended USE

Intended USERS

An optimal USER INTERFACE is one that meets USERS ’ needs U SABILITY ENGINEERING -related

USER research is essential to develop safe, usable, and satisfying MEDICAL DEVICES Therefore,

MANUFACTURERS should learn as much as practical about a MEDICAL DEVICE ’ S prospective

USERS by applying research methods that complement a MANUFACTURER ' S market research efforts The information collected from applying these research methods is typically used to help refine the preliminary USE SPECIFICATION

Recognizing that there are important differences between USABILITY ENGINEERING and market research focussing on a broader range of MEDICAL DEVICE development issues,

MANUFACTURERS should also conduct USER research with a USABILITY ENGINEERING focus

When conducting USER research that involves data potentially subject to security or privacy regulations, it is essential to adhere to these rules Additionally, a review by an Ethics Committee and obtaining informed consent may be necessary For further details, please refer to Annex F.

USERS can include: a) laypersons (e.g PATIENTS, laycaregivers or lay first responders); b) physicians; c) nurses; d) technicians (e.g radiological, IVD laboratory, dialysis, reprocessing); e) therapists; f) pharmacists; and g) emergency response personnel (EMTs, paramedics, medics)

In addition to the primary users, various other individuals play crucial roles, including assemblers, installers, trainers, transporters, biomedical and clinical engineers, maintenance and repair personnel, recyclers involved in decommissioning or end-of-service life handling, sterile processing staff, and administrative personnel.

After defining the intended USERS, the MANUFACTURER should document their common characteristics in the form of USER PROFILES

A USER PROFILE outlines the specific characteristics of a distinct USER GROUP, such as nurses It encompasses various attributes, including occupation, demographics (age, education, socioeconomic status, ethnicity, and cultural background), knowledge and skills (education, experience level, language proficiency, literacy, and health literacy), and potential limitations related to vision, hearing, cognitive abilities, dexterity, and mobility Additionally, it considers performance-shaping factors like learning styles and preferences, as well as work responsibilities linked to the TASKS associated with the MEDICAL DEVICE being developed.

A related concept to a USER PROFILE is called a persona A persona describes a fictitious USER

A persona can be tailored to focus on an individual, highlighting unique characteristics that a USER PROFILE may not capture Both personas and USER PROFILES can represent USERS with primary, secondary, or supplemental roles related to a MEDICAL DEVICE.

USER GROUPS can be derived from either concept

User groups are defined by shared characteristics, including mental, physical, and demographic traits that impact usability User profiles summarize these characteristics, with age being a key factor Categories may include children (ages 2 to 12), adolescents (ages 12 to 21), and adults (ages 21 and older) Additionally, it may be beneficial to create "senior" categories for individuals over specific age thresholds, such as 65, 70, 75, 80, or 85.

As individuals age, they may experience varying degrees of decline in cognitive and perceptual abilities Occupations that may be affected include roles such as physician, nurse, therapist, technician, patient, installer, and maintainer Additionally, prior experience with similar medical devices can influence user familiarity, with categories ranging from new users to those with extensive experience.

The classification of users based on experience includes three categories: trainees, inexperienced users with less than six months of experience, and experienced users with more than six months of experience It is important to note that the experience thresholds may differ depending on the specific type of medical device being utilized Additionally, the level of training can be categorized, with one example being users who have received training to operate the designated medical device.

(2) not trained to use the given MEDICAL DEVICE e) Education:

– categories based on educational level;

– general literacy or reading level; and

The MANUFACTURER might also segregate USERS based on special training, such as the advanced cardiac lifesaving training provided to critical care nurses or paramedics

Additional or alternative sorting criteria include native (i.e first) language, disability type, type of professional practice and USE ENVIRONMENT Establishing a manageable number of distinct

USER GROUPS calls for establishing primary USER and secondary USER differentiation factors

There is no rule regarding the optimal length of USER PROFILES, but they usually range from a few paragraphs to a couple of pages in length Annex G provides additional information on

Summative evaluations of medical devices should consider multiple distinct user groups, as the need for differentiation is context-dependent For instance, an insulin pen injector may cater to six specific user groups: caregivers, adolescents, adults, seniors, diabetes educators, and pharmacists Additionally, secondary characteristics such as visual impairments, hearing loss, cognitive challenges, and manual dexterity issues should be taken into account This approach ensures that each user group reflects a diverse representation of these secondary characteristics Furthermore, healthcare professionals may also require segmentation into more specific user groups to enhance the evaluation process.

Anticipated USER TASKS

In the initial phase of medical device development, defining anticipated user tasks is crucial before finalizing the design A task list can be created by analyzing similar and predecessor medical devices, as well as deriving insights from functional requirements and creative exercises This process aims to establish a general understanding of user interactions with the medical device, with further analyses available to refine the task list For more detailed information on task analysis, refer to sections E.1 9 and 9.2.

Intended USE ENVIRONMENT

Manufacturers must thoroughly analyze the intended use environments for medical devices, which are primarily utilized in hospitals, clinics, physician's offices, and patients' homes It is crucial to also consider alternative locations, such as ambulances and outdoor settings like campgrounds, especially when designing portable medical devices For more detailed information on use environments, refer to Annex H.

Work environments vary significantly, with critical care settings often bustling with noisy equipment and loud conversations, while physician's treatment rooms tend to be quieter and less active Important environmental factors to consider include lighting, vibration, temperature, humidity, precipitation, and architectural features like door dimensions For instance, operating a portable ventilator in an air ambulance presents challenges due to the dim lighting, limited space, and high levels of noise and vibration.

The description of the USE ENVIRONMENT should encompass various elements, including the physical environment with necessary protective gear such as gloves and eye protection, as well as heavy clothing It is essential to consider the lighting conditions and the ambient and intermittent sounds present Additionally, the roles of personnel and the nature of professional and social interactions, along with local or national variations in work organization, must be addressed The presence of additional equipment beyond the primary focus of the USABILITY project, as well as furnishings like chairs and cabinets that may create limited space or obstacles, should also be noted Furthermore, factors such as climate, including temperature and humidity, and potential distractions like telephone calls or requests for assistance are crucial to include in the overall assessment.

Meeting with prospective MEDICAL DEVICE USERS during the MEDICAL DEVICE development

PROCESS presents opportunities to learn about those USERS but also about the USE ENVIRONMENT and how it might affect USERS’ interactions with the MEDICAL DEVICE.

Recommended methods for developing the USE SPECIFICATION

informative) U SER INTERFACE REQUIREMENTS

Tiêu đề	IEC TR 62366-2:2016 - Guidance on the application of usability engineering to medical devices
Trường học	International Electrotechnical Commission
Chuyên ngành	Electrical and Electronic Technologies
Thể loại	Technical Report
Năm xuất bản	2016
Thành phố	Geneva

Định dạng
Số trang	106
Dung lượng	2,49 MB