4.1 Fieldwork took place between 18 th August and 15 th November 2008.
4.2 Prior to fieldwork commencing, all interviewers were briefed in person about the survey. The briefing was given by the Ipsos MORI project director and covered the following:
- introduction and background to the survey;
- the survey method;
- the survey questionnaire (with specific guidance on administering the CASI section);
- the potential for social desirability bias and the need to combat this; and
- survey administration.
Quality control and supervision
4.3 Quality control procedures were put in place to ensure all interviews were carried out to a high standard and that the selection of addresses was carried out appropriately.
4.4 At any one point during fieldwork, around 10% of interviewers were accompanied in the field by area managers and supervised as they undertook their interviews. This ensured that interviewers were not following poor practice and provided an opportunity for supervisors to give their colleagues advice on aspects such as maximising response rates.
4.5 10% of interviews on the survey were back-checked, whereby field staff contacted the respondents concerned to check that the interview had been carried out properly. This involved confirming the length of the interview, when it took place, and that key questions were asked accurately and coded. All of the back-checking was carried out by telephone and post, using contact information provided by respondents during their interview.
4.6 Because the survey was undertaken by Computer Assisted Personal Interviewing ( CAPI), there was no need for manual checking of completed questionnaires. As noted in the previous chapter, the CAPI script was set up to control for many of the errors that could have been made using a paper questionnaire (routing and logic checks in particular).
4.7 During fieldwork, progress updates were sent to the Scottish Government on a fortnightly basis detailing the number of interviews achieved and comparing this against the expected target for that stage in the fieldwork. Additionally, profile checks were run on the achieved interviews and sent to the Scottish Government. These checks compared the profile of the achieved sample against the target quotas set.