Epidemiologic Field Investigations using Epi Info:

1. Epidemiologic Field Investigationsusing Epi Info:

2. Learning Objectives By the end of this session, you should be able to: identify the different reasons for using check code write check code import check code from Epi 6 databases

3. Why use Check Code? Check Code is a series of commands that tell Epi Info that you want to do certain �checks� of your data as it is being entered. By using Check Code, you can protect your data against many common types of errors and make data entry easier. It is helpful when you have more than one person entering data.

4. Check Code Examples Use repeat fields Designate required fields Specify ranges to a field Specify legal or comment legal values Calculate fields Skip patterns of an interview

5. How do I create Check Code? There are two ways to create Check Code in Epi Info: Set the code in the Field Definition dialog box In MakeView, click on the �Program� button and begin to build (write) the code. Check Code should be created when you are creating and modifying your �view� using the MakeView program (i.e., before data entry).

6. Creating Check Codeby Field Definition Creating Check Code using the Field Definition: Repeat last Required Range Legal Values Comment Legal Values

7. Repeat Last A �repeat last� field minimizes entering the same response for multiple records (observations). The last value entered into a �repeat last� field will appear in subsequent records until a new value is entered. To create a �repeat last� field: Open the Field Definition dialog box when modifying a view. Check the box next to �Repeat Last�. Click �OK�. To remove this criterion, click the option again and unselect the checkbox.

8. Required Any data fields that must be completed can be set as �required� fields. Data entry will not be able to leave required fields blank or missing. To create a �required� field: Open the Field Definition dialog box when modifying a view. Check the box next to �Required�. Click �OK�. To remove this criterion, click the option again and unselect the checkbox.

9. Range By setting a field�s range, you can control the upper and lower limits of data that can be entered into a field (date and number fields only). Data entry will not accept any values outside the range you specify. To create a field with in a specified range: Open the Field Definition dialog box when modifying a view. Create the field as a number, date, time, or date/time. Check the �Range� box. Enter in the lower and upper values of the range. Click �OK�. To remove this criterion, click the option again and unselect the checkbox.

10. Legal Values Legal Values allow the user to specify that only certain responses will be �allowed� and entered. You can either create new responses, or take them from an existing table. To create legal values: Right-click to get the �Field Definition� box. Type the question or prompt. Select �Legal Values� button. Specify whether you want to create new responses (�CreateNew�) or take them from an existing table (�Use Existing Table�); if new, type in the responses as you want them to appear. Specify whether you want the responses sorted or unsorted (default = sorted).

11. Comment Legal Values Comment Legal Values allow the user to specify that only certain responses will be �allowed� and entered, but numeric codes can be stored rather than the text themselves. You can either create new responses, or take them from an existing table. To create comment legal values: Same as legal values, but precede the responses with a numeric value.

12. Field Types and Acceptable Check Code

13. Creating Check Codeusing Program Creating Check Code using the Program button: Conditional Jumps (�skip patterns�) Link and Code Fields Calculate values Creating dialog boxes to interact with user Check Code can be created to do many different tasks; these are just a few of the examples to demonstrate its use.

14. Tobacco Surveypg. 75, Alperin Text 5. Have you ever smoked at least a part of a cigarette? 1. Yes 2. No 8. Don�t Know 9. Refused to Answer If NO or DON�T KNOW or REFUSED, go to Question #9

15. Jumping to Another Field You can set a conditional jump using a Yes/No field (or any field). In order to do this, you must tell Epi Info: the field where the jump will occur the condition for the jump to occur the field to jump to if the condition is true Syntax: IF (condition) THEN (action) Example: IF Eversmk=(-) THEN GOTO Friends END

16. Jumping to Another Fieldon a Different Page In order to jump to another field on a different page, you must specify both. To jump to the first field on a specific page: To jump to the next page: GOTO +1 To jump to the previous page: GOTO -1 To jump to the nth page: GOTO n To jump to a specific field on a page: GOTO fieldname

17. Assign New Variables Check code can be used to link fields and automatically code between them. Example: Town Code and Town Name Enter a code ? a name gets entered Syntax: IF TownCode="4" THEN ASSIGN TownName="Marlboro" END

18. Assign New Variables Check code can be used to create or assign values for fields based on entry of other fields. Example: Age Enter Date of Birth ? Epi Info 2002 calculates age in years Syntax: ASSIGN Age=Years(DateofBirth,Systemdate) =Years(startdate,enddate)

19. Dialog Boxes Dialog boxes can provide guidance while entering data. One can create dialog boxes to: Look for a specific condition (or conditions), Display a message to the user Perform an action (in most cases, �clear� the current field) Example: Compare DateofBirth and TODAYDATE Syntax: IF DOB>TODAYDATE THEN DIALOG �Dates appear to be incorrect, double check� TITLETEXT = �Possible Error� CLEAR TODAYDATE GOTO TODAYDATE END

20. Dialog Boxes Dialog boxes can be created to do three things: Display information (Simple) Ask for and receive input (Get variable) Offer list for making choices (List of values) You can specify which one in the Dialog box under the �User Interaction� tab. Try them out on your own to see how they work!

21. Importing Check Code from Epi6 Check Code can be imported from a CHK file: From the MakeView menu, click on �Tools�. Select �Import Check Code�. Specify path and filename of the CHK file and the project file.

22. Summary of Topics Creating Check Code in Field Definition Creating Check Code using Program button Importing/Exporting Check Code