In CAPI data entry, consideration needs to be given to the properties of fields used in the application. The following table lists certain
field properties and how they might be used:
| Use enter key | This is usually selected, because otherwise the application will automatically advance to the next field, which might be confusing for the interviewer. |
| Mirror fields | These are very useful in CAPI applications, as they show the contents of fields in other forms. This can assist the interviewer. |
| Protected fields | CAPI applications use protected fields to show calculated or derived values. These provide useful feedback to the interviewer. |
| Force out-of-range | This is almost always turned off, since the interviewer should only be allowed to enter valid responses. However, you should consider including "not applicable", "don't know," and "refused" response categories. |
CAPI applications frequently make greater use of alphanumeric responses than do traditional key-from-paper systems. This is because of the interactive nature of CAPI, and it also makes the interview more interactive (by capturing names, for example).