The Scottish Health Survey 2024 - Volume 2: Technical Report

1.5   Fieldwork quality control and ethical clearance

1.5.1     Training interviewers

Interviewers new to SHeS were fully briefed on the survey’s content and procedures. Interviewers were supervised by an interviewer supervisor during the early stages of their work to ensure that interviews were administered correctly, and protocols were followed.

Interviewers that had worked on SHeS in previous years attended a refresher briefing ahead of the launch of the new survey year and were refreshed on any additional in-home processes when this was introduced. This ensured that they were aware of changes to survey content and procedures for 2024.

Interviewers interested in administering the biological module were initially screened for suitability. Minimum competency levels were set and only interviewers that met the set criteria were invited to training and accreditation sessions.

Full sets of written instructions, covering both survey procedures and measurement protocols, were provided to interviewers (measurement protocols are available on request from ScotCen).

1.5.2    Checking interviewer and measurement quality

A large number of quality control measures were built into the survey at the data collection stage and thereafter, to monitor the quality of interviewer performance.

Quality checks were carried out at 10% of productive households. These recalls checked with the participants that interviewers had followed the correct survey procedures when conducting the interview.

In addition to the above quality checking procedure, the computer program used by interviewers had in-built soft checks (which can be suppressed) and hard checks (which cannot be suppressed) associated with particular interview questions. When uncommon or unlikely answers were entered, or answers outside a predetermined range, these checks were triggered and appear as a warning message on the interviewers’ laptop. The interviewer is either encouraged to double-check the entered response (a soft-check) or asked to change it (a hard-check). For example, when young children were weighed by having an adult hold them; the weight of the adult on their own was entered into the computer followed by the combined weight of the infant and adult. A hard check was used to ensure that the weight entered for the adult alone did not exceed the weight of the infant and adult combined.

Soft-checks were similar to hard-checks, however they could be suppressed. For example, soft-checks were applied to height measurements; if an interviewer entered a respondent’s height to be in excess of 1.93 metres (6 feet 3 inches), a message appeared asking the interviewer to confirm that this entry was correct. The interviewer could suppress the soft-check once they had confirmed that the height entry was not a mistake.

1.5.3    Ethical clearance

Ethical approval for the 2024 survey, as for previous years, was obtained from the Health and Care Research Ethics Committee for Wales (REC reference number: 17/WA/0371).