Social desirability and interviewer bias may have been introduced by using interviewer-administered questionnaires.
The quantitative data were collected by using structured interviewer administered questionnaires; whereas key informant in-depth interview guide were developed for the qualitative study.
Baseline data collection was carried out using the pregnancy record, the child health development record and by using an interviewer administered structured questionnaire.
This problem is often mitigated by using bilingual interviewers and translated questionnaires.
Diet was assessed at years 0, 7, and 20 by using an interviewer-administered CARDIA diet history questionnaire (21).
We have previously used this practice [ 25], and learned that by using two interviewers, it is possible to utilise their abilities to bring different nuances to light.
A cross-sectional voluntary anonymous survey conducted from June 2008 to June 2009 recruited participants by using trained interviewers at 103 sites providing injecting equipment in mainland Scotland.
The data were collected by using pretested and interviewer administered questionnaire.
All data collection occurred via CATI by using trained telephone interviewers.
The data were collected by using pre-tested interviewer-administered structured questionnaires, which were adapted from related literatures.
