On average, the EIMS study administration group receives between 20-25 questionnaires per week from both cases and controls. Each questionnaire is carefully reviewed for any missing answers or unclear responses.

If any information is missing or unclear in the questionnaire the respondent is contacted on the telephone by someone in the administrative group and asked to respond to some parts of the questionnaire again.

When the questionnaire is complete all personal information about the respondent is removed, such as name, home address and Swedish personal number. The data from the questionnaire will thereafter be entered into the EIMS database.

All the information from the questionnaire is kept on a locked hard drive at Karolinska Institutet which is protected with the highest security. The hard drive is only accessible by persons who are employed in the EIMS study. Each person accesses the information using a personal identity card as well as a personal PIN number. The hard drive is only accessible when the Internet is switched off on the computer so that no information can leak out through viruses or be obtained through hacking.