Smoking, drinking and drug use 2021: Supplementary data quality information

Following the release of the Smoking, drinking and drug use among young people 2021 (SDD 2021), additional data quality work is being presented on the survey mode: school led versus interviewer led; and family affluence questions.

The SDD survey is normally conducted in schools by an Ipsos interviewer under exam conditions. However in 2021 due to the Covid-19 pandemic, schools were also offered the option to complete themselves. This report investigates more detailed information on the characteristics of the schools and pupils that participated in school led versus interviewer led survey administration.

Main findings [Tables 1 to 6]:

Schools in the North East (78%), South West (71%) and West Midlands (59%) were more likely to have used a school led delivery mode. Interview led survey mode was highest in London (78%) and the East of England (67%).

A higher proportion of pupils in the North East (78%), South West (69%), West Midlands (67%) and Yorkshire and the Humber (58%) participated in a school led survey. In London (83%) of pupils had an interviewer led survey.

The proportion of pupils participating in a school led interview was associated with deprivation, increasing from 44% in the least deprived quintile to 63% of pupils in the most deprived quintile.

Slightly more girls participated in school led surveys (52%) than boys (50%). The proportion of interviewer led surveys increased with age from 47% of 11 year olds to 56% of 15 year olds and 69% of 16 year olds.

As reported in the SDD 2021 annual publication data quality tables, there was a trend for pupils, in particular girls, to declare some more risky behaviours when the school led the survey themselves rather than an external interviewer. The more detailed information released in these tables helps to explain that much of these differences could be accounted for by surveying a higher proportion of older children, those from more deprived areas of the country and other factors associated with risky behaviours using the school led interview techniques.

Family affluence is measured as per the methodology used by the HBSC (Health Behaviour in School-aged Children), a research collaboration with World Health Organisation offices across Europe and North America: http://www.hbsc.org/

It uses the following questions to produce an overall family affluence ranking of low, medium or high:

• Do you have your own bedroom for yourself?
• Does your family have a dishwasher at home?
• How many times did you and your family travel outside of the UK for a holiday last year?
• How many computers (including laptops and tablets, not including game consoles and smartphones) does your family own?
• How many cars, vans or trucks does your family own?
• How many bathrooms (room with a bath/shower or both) are there in your home?

Due to the Covid-19 pandemic, the opportunity for families to travel outside the UK for a holiday was likely to be disrupted. Data tables 7 and 8 explore the change in response rates to the question on this question, and the impact this had on the family affluence scores between the 2018 survey and the 2021 survey.

In 2021, 61% of pupils answered that they had not travelled outside the UK for a holiday in the last year compared to 25% in 2018.

In 2021, a higher proportion of pupils were assigned Medium family affluence scores (58%) than in 2018 (50%). A smaller proportion of pupils were assigned a High family affluence score in 2021, (12%) compared to 24% in 2018.

Differences in patterns of risky behaviours between 2018 and 2021 survey outputs are likely to be in part a reflection of the Covid-19 pandemic restricting opportunities to holiday outside the UK and this being reflected in the family affluence calculations.