HM and PK organized the patient information session and help conduct the questionnaire.
Details of the language used to conduct the questionnaire were recorded.
Written instructions were provided to the researchers on sampling procedures, weight, height and waist circumference measurements, and how to conduct the questionnaire.
As an evaluation of participant opinions, ethical approval to conduct the questionnaire survey was not required, however appropriate ethical principles were considered at all stages.
Interviewers learn to conduct the questionnaire-assisted interview via intensive face-to-face training and to offer counselling by a trained person in case of knowledge gaps.
In addition, the evaluation was conducted during the holiday season, the busiest time of the year for the USPS, and we were permitted to conduct the questionnaire only with workers on the day shift (7 a.m.–3 p.m).
The operational manual included sufficient instructions on sampling procedures, weight, height, and WC measurements, how to conduct the questionnaire properly, and answers to some common questions that the field researchers might encounter during the actual data collection period.
Recruitment will be carried out by staff of the UK research networks (NIHR CRC DeNDRoN in England, NISCHR CRC in Wales, and SDCRN in Scotland), who will also conduct the questionnaire-based assessments.
‡Headache intensity on the day conducting the questionnaires.
After introducing ourselves and our research institute, closely explaining the nature of our research, and receiving verbal consent, we conducted the questionnaires in the participants' own surroundings.
