Data capture process of a self-administered questionnaire is inherently different from that of an interview. That has many implications on the settings in which data capture takes place. In a web interview (CAWI), the whole response process differs from that of an interviewer-administered interview. In CAWI respondent answers alone without any assistance or control, and sending the filled forms requires only a click of a button. In addition, the different implementations of web based data collection change the settings of responses process: in a static web questionnaire only a limited amount of checking can be implemented and most of checks are run only when the form is received in the web server. In an interactive questionnaire there is a lot more possibilities for checks and checks are run after a page has been sent and data is stored after each page. In an interactive questionnaire also question order can be defined which is not possible in a static form. The settings of the web based data collection produces such errors in data that do not exist in other modes.