Scoping and feasibility study to develop and apply a methodology for retrospective adjustment of alcohol consumption data Final Report October 2013 Authors: Part 1: Mapping of key changes in alcohol strength, standard measures, glass size and shape, 1990- 2012 Martine Stead, Linda Bauld, Kathryn Angus, Laura MacDonald Institute for Social Marketing, University of Stirling Marcus Munafò, Angela Attwood, Alia Ataya University of Bristol Part 2: Adjustment factors: development and application to survey data, 1990-2005 Elizabeth Fuller, Kevin Pickering NatCen Social Research Address for correspondence: Martine Stead Deputy Director Institute for Social Marketing University of Stirling and The Open University Stirling FK9 4LA Tel: 01786 467387 Email: [email protected] This research was undertaken by the authors as work of the Public Health Research Consortium. The Public Health Research Consortium is funded by the Department of Health Policy Research Programme. The views expressed in the publication are those of the authors and not necessarily those of the DH. Information about the wider programme of the PHRC is available from http://phrc.lshtm.ac.uk/ . [2] Table of Contents Executive Summary ...................................................................................................... 5 1 Mapping of key changes in alcohol strength, standard measures, glass size and shape, 1990-2012 ............................................................................................... 9 1.1 Introduction ....................................................................................................... 9 1.1.1 Background .................................................................................................... 9 1.1.2 Aims of the Research ..................................................................................... 9 1.1.3 Methodology ............................................................................................... 10 1.1.4 Structure of Part 1 ....................................................................................... 10 1.2 Data sources drawn on .................................................................................... 10 1.2.1 Legislation .................................................................................................... 11 1.2.2 HM Revenue & Customs data on duty ........................................................ 11 1.2.3 Alcohol manufacturers’ and retailers’ data ................................................. 11 1.2.4 Market research data .................................................................................. 11 1.2.5 Trade and hospitality press .......................................................................... 12 1.3 Changes in alcohol strength ............................................................................. 12 1.3.1 Definition of % ABV ...................................................................................... 13 1.3.2 Industry-led changes in ABV level ................................................................ 14 1.3.3 Market data broken down by ABV level ...................................................... 22 1.4 Changes in standard measures, glass size and shape ......................................... 30 1.4.1 Legislative changes in serving sizes in licensed premises ............................ 30 1.4.2 Use and popularity of different vessel sizes and types in licensed premises ....................................................................................................... 34 1.4.3 Changes in vessel size and type for home consumption ............................. 37 1.5 Summary ......................................................................................................... 39 1.5.1 Changes in alcohol strength ......................................................................... 40 1.5.2 Changes in standard measures, glass size and shape .................................. 40 2 Adjustment factors: development and application to survey data, 1990-2005 .................................................................................................... 42 2.1 Introduction .................................................................................................... 42 2.1.1 Methodology ............................................................................................... 42 2.1.2 Structure of Part 2 ....................................................................................... 43 [3] 2.2 Measuring alcohol consumption from survey data ............................................ 43 2.2.1 Sources of survey measures of alcohol consumption ................................. 43 2.2.2 Survey measures of alcohol consumption ................................................... 44 2.2.3 Calculating alcohol intake from drinks consumed ....................................... 44 2.2.4 Shortcomings of using survey data to estimate alcohol consumption ........ 46 2.3 Revised methodology ...................................................................................... 48 2.3.1 Beer .............................................................................................................. 48 2.3.2 Wine ............................................................................................................. 51 2.4 Impact and limitations of the revised estimates ............................................... 54 2.4.1 Impact of the revised estimates .................................................................. 54 2.4.2 Impact of revised estimates on drinking patterns by different groups ....... 56 2.4.3 Limitations ................................................................................................... 59 2.5 Summary of findings ........................................................................................ 60 2.6 Recommendations ........................................................................................... 60 REFERENCES .................................................................................................... 62 APPENDICES .................................................................................................... 63 1 Search Strategy ............................................................................................ 64 2 Market Data Sources ................................................................................... 65 3 Changes in Duty Levels: Summary of HMRC Information ........................... 68 4 Industry-led Changes in Product Strength, 1990-2012: Examples from the Alcohol & Hospitality Industries’ Trade Press .............. 72 5 Wine Market Country of Origin Tables ........................................................ 84 6 Use and Popularity of Different Vessel Sizes and Types in Licensed Premises: Examples from the Alcohol & Hospitality Industries’ Trade Press ................................................................................. 90 7 Changes in Glass Shape: Examples from the Alcohol & Hospitality Industries’ Trade Press .............................................................. 97 8 UK Glassware Market Data Tables ............................................................. 102 9 Summary of methodology ......................................................................... 105 [4] Executive Summary Background Harmful alcohol use is a serious public health issue (BMA 2008, Robinson & Lader 2009). To inform policy development in this area, an accurate understanding is needed of changes in real levels of alcohol consumption at population level over time. Changes in glass size and alcohol strength have complicated this understanding. For example, there has been a trend over the past 20-30 years towards larger measures, particularly of wine, being served in licensed premises, and towards stronger ABV (alcohol by volume) for certain categories of drink, such as lager, beer, cider and wine (NHS Information Centre 2010). Changes in glass shape (Attwood et al 2012) over recent years may also affect consumption estimates. These changes have made it difficult meaningfully to compare self-report consumption data over the same period, as the underlying assumptions and understanding regarding a standard drink or serving have not been consistent. Consistency is important, because assessing the effectiveness of population policy measures is only possible if data from different survey years are genuinely comparable. There is a need for new research to develop and apply a robust methodology for retrospective adjustment of official trend data on alcohol consumption, to take account of changes in glass size and shape and alcohol strength over time. Aims and methods A scoping and feasibility study was commissioned by the Department of Health through the Public Health Research Consortium (http://phrc.lshtm.ac.uk/ ) to research, develop and apply a methodology that allows for retrospective adjustment of alcohol consumption trend data in England, to take account of changes over time in glass sizes and shape and alcohol strength. The objectives of the study were to: a) Review available research and other evidence to map key changes in alcohol strength, standard measures, glass size and shape since 1990; b) Interview key stakeholders to establish relevant assumptions and to inform the mapping exercise; c) Develop a robust formula / formulae for use in retrospective adjustment of official data; d) Apply the formula /formulae to official data on a selective basis; and