Report
Gambling participation and the prevalence of problem gambling survey: Experimental statistics stage
Gambling Commission report produced by NatCen on the experimental statistics stage of the gambling participation and the prevalence of problem gambling survey.
Contents
- Executive summary
- Introduction
- Methodology and response
- Testing an alternative approach to the selection of participants within households
- - Introduction
- - Completion rates in responding households
- - Adherence to participant-selection instructions
- - Duplicate cases
- - Household clustering
- - Prevalence of gambling behaviours
- - Conclusion
- Measuring gambling-related harms
- Testing different approaches to asking questions about gambling participation
Response to the survey
You can view tables referenced in this section by downloading the file Tables A1 to A48 - Gambling Survey - Experimental statistics stage (XLSX)
Step 1 response
Address-level response rates
Table A.1 (Step 1 address-level response) summarises step 1 address-level response rates.
In total 21,953 addresses were issued. In remote surveys (that is where participants complete the survey independently without any involvement from an interviewer), no information is known about the reason for non-response in individual addresses. However, it was assumed that around 9 percent of addresses in the sample (1,976) were not residential and were therefore ineligible to complete the survey12.
In total, 3,563 addresses were productive. The adjusted address-level response rate, that is the proportion of eligible addresses where a questionnaire was completed by at least one adult in eligible addresses, was 18 percent (lower than the target of 22 percent). There was no response from 16,226 of the addresses assumed to be eligible and an individual from a further 188 addresses contacted the office to say they did not wish or were unable to take part.
Table A.2 (Step 1 address-level response, by experimental condition) summarises the response rate for households, split by the experimental condition (such as whether a maximum of two or four adults were invited to take part).
In total, 2,396 C1 (up to two adults) addresses were productive. This gives a household response rate of 18 percent for the assumed eligible addresses, under the target of 22 percent. Of these 2,396 productive households, 1,276 (53 percent) yielded one fully productive adult and 1,120 (47 percent) yielded two fully productive adults.
In terms of C2 (up to four adults) addresses, 1,167 were productive. This gives a household response rate of 17 percent for the assumed eligible addresses, similar to that achieved for the C1 (up to two adults) addresses. Of these 1,167 productive households, 668 (57 percent) yielded one fully productive individual participant. 408 (35 percent) yielded two, 89 (8 percent) yielded three and two households (less than 0.5 percent) yielded four fully productive adults.
Table A.3 (Step 1 address-level response, by country) shows the breakdown of the issued step 1 sample in England, Scotland and Wales and the household response rate in each country.
In total, 86 percent of the issued addresses were in England, 9 percent in Scotland and 5 percent in Wales. Household responding rates were very similar across all three countries: 18 per cent in England, 18 per cent in Scotland and 19 per cent in Wales.
In terms of the English regions, the highest response rates were achieved in the South West (21 percent) and East Midlands (20 percent) and the lowest in London (13 percent) (Table A.4, Step 1 address-level response, by Government Office Region).
As stated previously, power calculations assumed that in C1 households where two adults were invited to take part, an average of 1.4 participants would do so. In C2 households where up to four adults were invited to take, an average of 1.5 would do so. As can be seen in Table A.5 (Step 1 experimental condition means), these assumptions were borne out in step 1: C1 (up to two adults) households had an average of 1.47 completions whilst C2 (up to four adults) had an average of 1.51.
Individual-level response rates
Following the process of removing duplicate responses, cases deemed to have completed the online questionnaire too quickly to have properly engaged with the questions and cases above the maximum defined number of completions (two or four) for that household, it was assumed that all responses in the dataset were from 5,275 unique individuals who had completed the questionnaire.
Table A.6 (Step 1 individual response, by age and sex) shows the age and sex profile of the 5,275 responding adults who completed the step 1 questionnaire (2,336 men, 2,935 women and four participants who did not respond to the age and/or sex questions).
In total, 44 percent of the responding unweighted sample were men and 56 percent were women. This under-representation of men is similar to that seen in the latest published results for other surveys with the same completion modes, for example, the Public Confidence in Official Statistics (PCOS) 2021 by the National Centre for Social Research (opens in new tab). In total, 46 percent of the PCOS 2021 unweighted main sample were men and 54 percent women.
Those in the younger age groups were less likely to take part than their older counterparts: 6 percent of responding adults were aged 18 to 24 years (this age group makes up 10 percent of the adult population of Great Britain) and 19 percent were aged 65 to 74 years (this age group makes up 13 percent of the adult population of Great Britain).
This difference was particularly pronounced for men: 5 percent of the male sample were aged 18 to 24 years (this age-sex group makes up 11 percent of the male adult population of Great Britain). The equivalent proportions for women aged 18 to 24 years were 7 percent and 10 percent. The national percentages are based on the 2021 mid-year population estimates for Great Britain: Estimates of the population for the UK, England, Wales, Scotland and Northern Ireland by the Office for National Statistics (ONS) (opens in new tab).
As recommended from the pilot, the minimum age of completion was raised from 16 to 18 years of age. Whilst this youngest age group are still underrepresented; it was less so than was seen in the pilot.
Table A.7 (Step 1 individual response by mode of completion, experimental condition and sex) summarises the individual response rate for the two completion modes (online and postal), split by experimental condition (that is whether up to two or up to four adults were asked to take part in the survey), and by sex.
Of the 5,275 questionnaires included in this analysis: 3,316 (63 percent) were completed online and 1,959 (37 percent) were completed on paper and posted back. The proportion of participants completing the questionnaire online was very similar across the two experimental conditions, 63 percent in the C1 (up to two adults) addresses and 62 percent in the C2 (up to four adults) addresses.
Step 2 address-level response rates
Address-level response rates
Table A.8 (Step 2 address-level response) summarises the address-level response rates for step 2. At this step up to two adults were asked to take part in all 14,982 issued addresses.
In total, 1,348 addresses (9 percent of the issued sample) were assumed to be ineligible (non-residential) and 2,405 addresses were productive. The adjusted address-level response rate, that is the proportion of eligible addresses where a questionnaire was completed by at least one adult in eligible addresses, was 18 percent (same as the response rate achieved at step 1 but lower than the target of 22 percent).
There was no response from 11,057 of the addresses assumed to be eligible and an individual from a further 172 addresses contacted the office to say they did not wish or were unable to take part.
Table A.9 (Step 2 address-level response, by country) shows the breakdown of the issued step 2 sample in England, Scotland and Wales and the household response rate in each country.
In total, 86 percent of the issued addresses were in England, 9 percent in Scotland and 5 percent in Wales. Household responding rates were similar across all three countries: 18 per cent in England, 19 per cent in Scotland and 16 per cent in Wales.
In terms of the English regions, the highest response rates were achieved in the South East (20 percent) and South West (20 percent) and the lowest in London (13 percent) (Table A.10 Step 2 address-level response, by Government Office Region).
Individual-level response rates
Following the processes of removing duplicate responses, cases deemed to have completed the online questionnaire too quickly to have properly engaged with the questions and cases above the maximum defined number of completions (two adults), it was assumed that all responses in the dataset were from 3,549 unique individuals who had completed the questionnaire.
Table A.11 (Step 2 individual response, by age and sex) shows the age and sex profile of the 3,549 responding adults (1,594 men, 1,949 women and six participants who did not respond to the question) who completed the questionnaire.
In total, 45 percent of the responding unweighted sample were men and 55 percent were women. Those in the younger age groups were less likely to take part than their older counterparts: 6 percent of responding adults were aged 18 to 24 years (this age group makes up 10 percent of the adult population of Great Britain) and 19 percent were aged 65 to 74 years (this age groups makes up 13 percent of the adult population of Great Britain).
The Great Britain population estimates are based on the 2021 mid-year data from the Estimates of the population for the UK, England, Wales, Scotland and Northern Ireland by the Office for National Statistics (ONS). This difference was again particularly pronounced for men: 5 percent of the male sample were aged 18 to 24 years (this age-sex group makes up 11 percent of the male adult population of Great Britain). The equivalent proportions for women aged 18 to 24 years were 6 percent and 10 percent.
Table A.12 (Step 2 individual response, by mode of completion and sex) summarises the individual response rate for the two completion modes (online and postal).
Of the 3,543 questionnaires included in this analysis: 2,228 (63 percent) were completed online and 1,315 (37 percent) were completed on paper and posted back. These are the same proportions found for the step 1 sample.
There was no difference between men and women in the mode of completion (63 percent for online completions and 37 percent for postal completions for both groups). However, there was a marked difference according to age with the percentage of those completing the survey online decreasing with age (and hence the percentage completing the postal questionnaire increasing with age).
In all age groups, except the oldest two (aged 65 to 74 years and aged 75 years and over), a higher proportion completed the survey online rather than filling in the postal questionnaire. In total, 29 percent of those aged 75 years and over and 40 percent of those aged 65 to 74 years completed the survey online compared with between 58 percent and 90 percent of those in the younger age groups (Table A.13 Step 2 individual response, by mode of completion and age).
Use of Quick Response (QR) codes to facilitate online participation
The invitation and reminder letters for the 2021 pilot and step 1 of this experimental statistics phase included a short survey Uniform Resource Locator (URL) and individual eight-character access codes for participants to manually enter into a browser and access the survey.
In step 2, two QR codes were also included as an alternative way for participants to access the survey. The QR codes, when scanned, took participants straight into the online questionnaire, bypassing the need to manually enter any access information.
Uptake of the QR codes was high: 52 percent of those completing the survey online did so via the QR code and 48 percent accessed the survey via manually entering the survey URL and typing in the access code.
As discussed in the previous section, the percentage of those completing the survey online decreased with age. Within online completions, this pattern was replicated for the use of QR codes: 73 percent of those aged 18 to 24 years accessed the survey via a QR code compared with 19 percent of those aged 75 years and over ('Figure 3: Age profile and access mode of those completing the survey online' as follows).
Figure 3: Age profile and access mode of those completing the survey online
| Access and completion mode | 18 to 24 years of age (percentage) |
25 to 34 years of age (percentage) |
35 to 44 years of age (percentage) |
45 to 54 years of age (percentage) |
55 to 64 years of age (percentage) |
64 to 75 years of age (percentage) |
75 plus years of age (percentage) |
Total (percentage) |
|---|---|---|---|---|---|---|---|---|
| Via QR codes | 73% | 66% | 65% | 56% | 40% | 20% | 19% | 52% |
| Via URL and access code | 27% | 34% | 35% | 44% | 60% | 80% | 81% | 48% |
| Bases (unweighted) (number) | 179 | 436 | 466 | 400 | 363 | 264 | 121 | 2,229 |
References
12 When estimating the proportion of ineligible addresses on an online survey, it is best practice to assume the same ineligibility rate as a recent face-to-face survey which uses the same sampling frame and sampling approach and for which detailed outcomes are known for the entire issued sample. Ineligibility rates in Postcode Address File (PAF) face-to-face surveys tend to fall between 8 percent and 10 per cent. 9 percent is the rate recorded in the most recent face-to-face British Social Attitudes Survey (2019) and has been used as an appropriate default for this survey.
Questionnaire content and design
Last updated: 27 July 2023
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Formatting changes corrected only.