Hướng dẫn tạo bộ câu hỏi trong EpiData

EpiData II• Simple surveys – one questionnaire • Complicated surveys – few questionaires If there is ID – possible to merge data... Creating Questionnaire • Define Data • Can either open

EpiData (I)

• Creating questionnaire

• Controlled data entry

• Documenting and printing data

• Correction of questionnaires, records

• Comparing of 2 data files

• Importing and exporting data

• Simple analysis

EpiData (II)

• Simple surveys – one questionnaire

• Complicated surveys – few questionaires

If there is ID – possible to merge data

– Any defined checks

• Other notes or log files

Creating Questionnaire

• Define Data

• Can either open QES file or create one

Structure of questionnaire

Three sections:

– Field name (variable)

– Text describing field

– Input definition (number/ letters/ date)

Field name (variable)

• No more than 10 characters

• Begin with a letter

• No spaces or punctuation marks

Field Name (II)

– Uses first 10 letters

Childquest Child questionnaire <Y>

Automatic field names

• Text in curly brackets { } used in

preference

• Common words skipped (what, the, and, etc.)

• If question starts with number, “N” is

inserted before the number

Automatic field names,

examples

Did you {eat ice cream} EATICECREAM

Variable type

• Define variables using “Pick List” or “Code writer”

• Choose type of variable:

Text variables

• Information of text and/or numbers

• Holding information (e.g names, addresses)

• UPPER CASE

– Can only hold upper case (capital) letters

– Lower case variable automatically converted into upper case text (ex: Egypt converted into EGYPT)

• No mathematical operations

• Length (How many characters)

• <_>

– Hold information on dates

– Data in american <MM/DD/YYYY>

– European <DD/MM/YYYY>

• Soundex:

– Coding of words (anonymous, eg A-123)

– Code to limit orthographic errors (eg Rome and Roma) – <S >

System variables

• Values generated automatically

• Today date: date of the data entry

Save Questionnaire

• Preview data

• Save questionnaire

– Creates QES file

• Create Data file

– Click Make Data file button > Make Data file – Creates .REC file

• Questionnaire and Data file ready

• But……

Errors in data entry

• Tranposition (ex: 39 becomes 93)

• Copying errors (0 copy as an “o” letter)

• Consistency errors: two or more responses are contradictory (sex: man, pregnancy=Yes)

• Range errors: answers outside of probable or possible values (ex: heigh = 3 metres)

Preventing errors

• Standardised and previously tested questionnaire

• Training the interviewers and data entry clerck

• Checking and validating paper forms of the

questionnaires

• Checking during the data entry (Check module Data)

Epi-• Validation: entering twice data by different operators

• Checking after data entry (Analysis module Epi-Info)

Checks (I)

• Reduce errors in input

• Checks help with data entry

• Many different types

• Examples:

– Limit entry of numbers to specific range

– Forcing entry to be made in field

Checks (II)

• Once Data file is created:

• Click Checks button > choose .REC file

Checks (III)

• Range, legal:

– 1-3, 9

– First range then individual numbers

– Tallinn, Riga, Vilnius

– Fixing only min or max value

• - INF-5 (all numbers inferior or equal 5)

• 0-INF (all positive numbers superior or equal to 0)

Checks (IV)

• Repeat:

– Show data from previous record

• Value Label

– Add text to explain values

– Click + to add label

– Format as shown

– Press F9 during data entry

to see labels

Data Entry (I)

• Click Enter data button

> choose .REC file

• Dates:

– 15/5/2006 – type 150506 or 15/5/06

• Value Labels:

– Press F9 to view

Data Entry (II)

• Record navigation:

• Delete records:

– Click cross to delete

– Record marked for deletion, but can be recovered

Document Tools

• File Structure

• Data entry notes ( NOT file)

– Use to write comments during data entry eg: difficult to read handwriting etc

• View Data

• List Data

• Codebook

– Basic descriptive statistics on all variables

• Validate duplicate files

– Check consistency after double entry

Export to other programs

• Click Export data button

• Choose program

• Including Excel, Stata, SPSS

• For Epi-info open .REC file directly

• Lauritsen JM & Bruus M EpiData (version 3.1) A

comprehensive tool for validated entry and

documentation of data The EpiData Association,

Odense Denmark, 2004.

• Lauritsen JM, Bruus M EpiTour - An introduction to

validated dataentry and documentation of data by use of EpiData The EpiData Association, Odense Denmark, 2005.

www.epidata.dk