FHRS Audit 2021 Technical report: Telephone fieldwork

Cognitive testing

Between 14 September and 27 September, 2021, 10 cognitive interviews were conducted with food businesses to test the first draft of the questionnaire. These interviews involved running through the survey as it would be delivered during mainstage fieldwork, with follow-up discussions at the end of the survey to check the respondents’ understanding of terminology and the extent to which it was easy or difficult to answer questions. 

The survey performed well during cognitive interviews. Participating food businesses typically understood the questions asked and were able to answer them with relative ease. However, there were some questions where potential issues were identified and/or where improvements were recommended by participants. Small changes were therefore made to the questionnaire ahead of pilot fieldwork.   

Pilot fieldwork

Between 20 October and 22 October, 2021, IFF Research piloted the ECS with 50 businesses. Table 4.1 presents the number of interviews completed by county, sector and FHRS rating. 

Table 4.1 Profile of pilot interviews with food businesses

Country

Sector

FHRS Rating

Prior to the commencement of pilot fieldwork all interviewers received a briefing on the survey and were issued with written instructions, providing them with an understanding of the background to the research, the questionnaire design, the screening criteria and the sample design.

The pilot survey involved administering the survey exactly as it would be during mainstage fieldwork. As well as allowing for further checks on comprehension of questions and survey flow, the pilot provided an opportunity to monitor response patterns and the overall interview length. 

The results of the pilot were positive in that: the average duration was in line with the target duration; there were no issues with the screening process; there was limited feedback from interviewers regarding issues with participant comprehension; and businesses were generally willing to participate.

Following the completion of pilot fieldwork, minor refinements were made to the questionnaire to improve the clarity of questions asked and to add pre-coded responses that were not previously included. The final version of the questionnaire used in mainstage fieldwork can be found in Appendix B of this report.

Mainstage fieldwork

Mainstage fieldwork was carried out between November 15th and December 14th ,2021. A total of 1,500 food businesses were interviewed. Table 4.2 presents the number of interviews completed by county, sector and FHRS rating.

Table 4.2 Profile of mainstage interviews with food businesses

Country

Sector

FHRS Rating

As with the pilot, prior to commencement of mainstage fieldwork all interviewers received a briefing on the survey and were issued with written instructions. This ensured that interviewers understood the background to the research, the questionnaire design, the screening criteria and the sample design.

Checks were conducted on the final 1,500 interviews to ensure the data was robust before the beginning of analysis. This involved conducting data validation checks and identifying outlier responses.   

Response rate

A total of 11,518 records, acquired from the FSA’s FHRS database, were used over the course of the survey with food businesses. Of these, 419 records were ineligible, as the business reported that they did not sell, serve or prepare food for the public (361) or because the business was closed (58). 

Of the remaining 11,099 businesses, a further 9,082 records were in scope of the study, but not in the scope of fieldwork. For example, 6,374 records could not be reached during the fieldwork period and a further 1,401 records had an appointment set that could not be achieved in the fieldwork period (see table 4.3). 

Table 4.3 Survey outcome for sample in scope of the study 

Response rate calculations do not include records that were outside of the scope of the fieldwork, given that no firm contact was made with these food businesses. This means that 2,017 records were in scope of fieldwork. Of these, 1,500 completed an interview. This equates to a response rate of 74% (see Table 4.4).

Table 4.4 Survey outcome for sample in scope of the fieldwork

Overlap between the audit and telephone survey of food businesses

Of the 1,522 food businesses covertly audited, 272 also participated in the telephone survey. Table 4.5 presents the profile of these food businesses in terms of country, sector and FHRS rating. 

Table 4.5 Profile of food businesses both audited and surveyed

Country

Sector

FHRS Rating

The profile of the businesses that were both audited and surveyed broadly reflects the profile of the underlying population of businesses in terms of sector and FHRS rating. However, owing to the purposeful oversampling of Northern Irish and Welsh food businesses to ensure that robust base sizes were achieved for each country, the split between England, Northern Ireland and Wales differs from the underlying population.