Background

The Health Survey for England (HSE) was designed to estimate the proportion of people in England who have health conditions, and the prevalence of risk factors and behaviours associated with certain health conditions among the population and to monitor trends in these risk factors and behaviours. The surveys provide information about adults aged 16 and over, and children aged 0 to 15, living in private households in England. For more information see Health Survey for England.

The way alcohol consumption is measured in surveys needs to adapt to changes in real-world alcohol consumption. The method used by the Health Survey for England to convert drinks to alcohol units remained essentially unchanged from 1991 to 2005, based on assumptions introduced by the General Household Survey (GHS) in 1990 (source: ONS).

In 2006, changes were made to the way HSE and other surveys estimate alcohol consumption. The revised methodology has been used from 2006 onwards and was summarised in the Appendix-changes in the conversion of drink to alcohol units in HSE 2019 Adult health behaviours report.

In June 2018, the alcohol theme group of the English Health Statistics Steering Group (EHSSG) hosted a workshop with alcohol consumers and experts to consider the need for updating and further harmonisation of government survey questions relating to alcohol consumption. The workshop concluded that there was a need to consider updating the product list and conversion table used in the HSE and to consider whether new questions were needed to reflect current alcohol drinking behaviours and policy concerns.

The HSE Alcohol Working Group was formed in 2019 with the following aims:

• update the alcohol product list that HSE participants are asked about
• review the current alcohol unit conversion factors
• consider whether new questions are needed to reflect current policy.

A series of recommendations were put forward following this review, including the suggestion to update the alcohol unit conversion factors

1. Implement new unit conversion factors for cans of beer, lager and cider
2. Retain the existing assumption of 12.5% alcohol by volume (ABV) for wine when converting drink consumption into units of alcohol
3. Round the conversion factors (in units of alcohol) to one decimal place rather than the current method which rounded to the nearest 0.5 units.

This report presents analysis comparing published estimates in the HSE 2019 and HSE 2021 reports, with estimates using the same data with the above three recommendations applied (that is, different conversion factors, and units rounded to 0.1 rather than 0.5). This was done ahead of the proposed changes being used in the HSE 2022 Adult drinking report.