Survey response

Scotland level

The final number of social survey interviews achieved was 10,471. This is above the target of 10,450 interviews and represents an overall response rate of 47%. The conversion from household interview to random adult completion was 92%.

Standardised outcome codes (based on an updated version of those published in Lynn et al (2001)) for survey fieldwork were applied across the Scottish Household Survey, Scottish Health Survey and Scottish Crime and Justic Survey. The outcome codes paper includes guidance on the appropriate categorisation of interview outcomes.

Table 3 gives a detailed breakdown of the SHS response for all sampled addresses for Scotland. The addresses of unknown eligibility have been allocated as eligible and ineligible proportional to the levels of eligibility for the remainder of the sample. This approach provides a conservative estimate of the response rate as it estimates a high proportion of eligible cases amongst the unknown eligibility addresses.

For 2024, Ipsos quality assurance procedures also identified falsified interview information relating to one interviewer. As a result all unverified interviews conducted by this interviewer were removed from the data, resulting in the loss of 117 records from the final data - primarily in South Lanarkshire and Glasgow City.

Table 3: Fieldwork outcomes

Table 4 shows how response rates have changed over time. Adjusted response rates (response rates where sample is net of unreachable addresses such as unoccupied houses) were not possible to calculate for 2020 and 2021.

Table 4: Response rates by year

The response rate dropped considerably between 2019 and 2022. However, this was partly due to a decision to scale back the use of reissues. Only 6.2% of SHS addresses were reissued in 2022, compared with 40.5% in 2019. The first issue response rates were 51% in 2019 and 43% in 2022. So, between 2019 and 2022, there was a less dramatic drop in first issue response rates (8 percentage points) than in final response rates (19 percentage points).

The decision to scale back the use of reissues was based on an assessment of the impact of reissuing on survey estimates. The assessment found that reissuing had a minimal impact on survey estimates, and was therefore not a cost-effective way of reducing non-response bias.

Local authority level

Table 5: Response rate by local authority

Monitoring and reducing the respondent burden

The Code of Practice for Statistics states that "Statistics producers should be transparent in their approach to monitoring and reducing the burden on those providing their information, and on those involved in collecting, recording and supplying data." Furthermore it states that "The burden imposed should be proportionate to the benefits arising from the use of the statistics."

The following steps are/have been taken to reduce respondent burden.

• Addresses selected for any of the surveys (SHS, SHeS, SCJS) are removed from the sample frame for a minimum of 4 years so that they cannot be re-sampled for another survey.
• Samples sizes are no greater than required to obtain robust local authority estimates.
• In advance of the 2024 Scottish Household Survey, a questionnaire review was carried out, with the aim of shortening the interview from 1 hour to 45 minutes.
• The SHS social interview is carried out using Computer Aided Personal Interviewing (CAPI). Routing is built into the CAPI script which ensures that respondents are only asked questions that are relevant to them, e.g. respondents are only asked questions on mortgage repayments if they have a mortgage.

Interviewer briefings are held annually. These events provide interviewers with an opportunity to feedback on improvements that could be made to the questionnaire, to assist them conducting interviews and reduce the burden on respondents.

Physical survey

Just over half of the SHS sample (54.7%) was assigned to the physical survey module. For completion of the physical survey, respondents had to agree to make an appointment for a surveyor to make a follow-up visit and to complete the appointment.

There was a target of at least 80 completed physical surveys for each local authority along with a target of 3,004 surveys for Scotland. The 2,905 surveys achieved for Scotland in 2024 did not exceed the target of 3,004 and there were fewer than 80 physical survey responses for 17 local authorities.

Table 6: Physical survey response rate