A review of the validity and reliability of alcohol retail sales data for monitoring population levels of alcohol consumption: a Scottish perspective

An investigation into patterns of Alcohol drinking in Scotland after the introduction of minimum unit pricing

BACKGROUND

In 2018, Scotland became the second country to implement minimum unit pricing (MUP) for all types of alcoholic beverages. The aim of this study was to examine the effect of the policy.

METHOD

Three national household-level surveys were used: Scottish Health Surveys (2008-2021), Health Surveys in England (2011-2019), and Northern Ireland Continuous Household Survey (2011-2015). First, a generalized ordered logistic model examined patterns of drinking solely in Scotland from 2008-2021 covering current drinking, drinking categories and the weekly consumption (in alcohol units). Secondly, difference-in-difference (DID) analysis was employed to examine changes in "social drinking" behaviours in Scotland after the announcement in 2012 (2011-2015, Northern Ireland and England as comparators) and after the adoption of the policy in 2018 (England as a comparator, with two timeframes 2016-2019 and 2013-2019).

RESULTS

Overall, drinking in Scotland began to decline prior to 2012 and dropped further with the enactment of MUP in 2018. In response to MUP, the likelihood of abstention increased along with a slight decrease in the prevalence of heavy drinking. The overall amount of drinking fell by about 8% after 2012 and 12% after 2018 (as compared to 2008-2011 level), with a significant decline seen in moderate drinkers but not of those who drank at hazardous or harmful levels. The DID analyses confirmed the reduction in current drinking in Scotland starting since 2012 and continued post-MUP in 2018.

CONCLUSION

This study points to the impact of MUP in Scotland with a potential role for 'policy signalling' by the Scottish Government's with a multiple-buy discount ban and MUP's announcement since 2011-2012. Indications of impact include a clear decline in alcohol consumption levels and a small but noteworthy change in prevalence of overall drinking and heavy drinking.

The estimated health impact of alcohol interventions in New Zealand: A modelling study

AIMS

To estimate the health impacts of key modelled alcohol interventions among Māori (indigenous peoples) and non-Māori in New Zealand (NZ).

DESIGN

Multi-stage life-table intervention modelling study. We modelled two scenarios: (1) business-as-usual (BAU); and (2) an intervention package scenario that included a 50% alcohol tax increase, outlet density reduction from 63 to five outlets per 100 000 people, outlet hours reduction from 112 to 50 per week and a complete ban on all forms of alcohol marketing.

SETTING AND PARTICIPANTS

The model's population replicates the 2018 NZ population by ethnicity (Māori/non-Māori), age and sex.

MEASUREMENTS

Alcohol consumption was estimated using nationally representative survey data combined with sales data and corrected for tourist and unrecorded consumption. Disease incidence, prevalence and mortality were calculated using Ministry of Health data. We used dose-response relationships between alcohol and illness from the 2016 Global Burden of Disease study and calculated disability rates for each illness. Changes in consumption were based on the following effect sizes: total intervention package [-30.3%, standard deviation (SD) = 0.02); tax (-7.60%, SD = 0.01); outlet density (-8.64%, SD = 0.01); outlet hours (-9.24%, SD = 0.01); and marketing (-8.98%, SD = 0.02). We measured health gain using health-adjusted life years (HALYs) and life expectancy.

FINDINGS

Compared with the BAU scenario, the total alcohol intervention package resulted in 726 000 [95% uncertainty interval (UI) = 492 000-913 000] HALYs gained during the life-time of the modelled population. Māori experienced greater HALY gains compared with non-Māori (0.21, 95% UI = 0.14-0.26 and 0.16, 95% UI = 0.11-0.20, respectively). When modelled individually, each alcohol intervention within the intervention package produced similar health gains (~200 000 HALYs per intervention) owing to the similar effect sizes.

CONCLUSIONS

Modelled interventions for increased alcohol tax, reduced availability of alcohol and a ban on alcohol marketing among Māori and non-Māori in New Zealand (NZ) suggest substantial population-wide health gains and reduced health inequities between Māori and non-Māori.

Is minimum unit pricing for alcohol having the intended effects on alcohol consumption in Scotland?

BACKGROUND AND AIMS

The Scottish Government introduced minimum unit pricing (MUP) for alcohol on 1 May 2018. This means retailers in Scotland cannot sell alcohol to consumers for less than £0.50 per unit (1 UK unit = 8 g ethanol). The Government intended the policy to increase the price of cheap alcohol, cut alcohol consumption overall and particularly among those drinking at hazardous or harmful levels, and ultimately reduce alcohol-related harm. This paper aims to summarise and assess the evidence to date evaluating the impact of MUP on alcohol consumption and related behaviours in Scotland.

ARGUMENT

Evidence from analyses of population-level sales data suggest, all else being equal, MUP reduced the volume of alcohol sold in Scotland by ~ 3.0% to 3.5%, with the largest reductions affecting cider and spirits sales. Analyses of two time series datasets on household-level alcohol purchasing and individual-level alcohol consumption suggest reductions in purchasing and consumption among those drinking at hazardous and harmful levels, but offer conflicting results for those drinking at the most harmful levels. These subgroup analyses are methodologically robust, but the underlying datasets have important limitations as they rely on non-random sampling strategies. Further studies identified no clear evidence of reduced alcohol consumption among those with alcohol dependence or those presenting to emergency departments and sexual health clinics, some evidence of increased financial strain among people with dependence and no evidence of wider negative outcomes arising from changes in alcohol consumption behaviours.

CONCLUSIONS

Minimum unit pricing for alcohol in Scotland has led to reduced consumption, including among heavier drinkers. However, there is uncertainty regarding its impact on those at greatest risk and some limited evidence of negative outcomes, specifically financial strain, among people with alcohol dependence.

A measure of alcohol affordability for Sweden: Capturing trends among different demographic groups

The World Health Organization has rated alcohol abuse as one of the leading risk factors for population health worldwide and emphasises the relevance of alcohol affordability (AA) measures as important instruments to monitor alcohol control policy. The present study suggests an AA index that is suitable for measuring AA in Sweden, where off-premises alcohol is exclusively distributed by Systembolaget, the government-owned chain of liquor stores. Sweden provides uniform off-premises prices for alcohol and extensive register data, which profits the accuracy of this index. By allowing for AA comparisons across types of alcoholic beverages (beer, wine, spirits) and price categories, as well as across population groups (age, sex and family composition), and by being transferable to other Nordic countries with uniform off-premises prices, this study will facilitate governmental monitoring and supervision of the alcohol policy in Nordic countries. The suggested AA index is defined as the ratio of the median equivalised disposable income and the price per litre of 100% ethanol for alcohol, scaled to equal 100% in the base year. The income can be measured for the reviewed population or a subgroup, and the price measure can include all sold alcoholic beverages or separate them by beverage type and/or price category. Thereby, the index measures the number of litres of 100% ethanol that are affordable with the median income. Applying the index to the publicly available data for 2011-2019 from Statistics Sweden and Systembolaget reveals that alcohol in Sweden generally became more affordable, with high-priced alcoholic beverages becoming comparably more affordable than low-priced alcohol. However, low-priced beer became less affordable over the last decade. Future studies may validate the AA index against alcohol consumption.

When the pubs closed: beer consumption before and after the first and second waves of COVID-19 in Australia

AIMS

Restrictions to alcohol availability during the first and second waves of the COVID-19 pandemic in Australia included closures of businesses where alcohol is sold for on-premises consumption (pubs, bars, restaurants and cafes), but not where alcohol is sold for off-premises consumption (take-away and home delivery). This study aimed to compare beer consumption before and after restrictions to alcohol availability during the first and second waves of COVID-19 in Australia.

DESIGN

Interrupted time-series analysis.

SETTING

Australia.

PARTICIPANTS

Estimated resident population aged 15+ years.

MEASUREMENTS

Seasonally adjusted estimates of beer per capita consumption measured in litres of alcohol (LALs) per week, disaggregated by on- and off-premises sales.

FINDINGS

First-wave restrictions (week beginning 23 March 2020) were associated with a significant immediate reduction in on-premises beer per capita consumption [-0.013 LALs, 95% confidence interval (CI) = -0.013 to -0.012, P = < 0.001], but no significant change in off-premises beer per capita consumption. Partial removal of first-wave restrictions (week beginning 18 May 2020) was associated with a significant immediate increase in on-premises beer per capita consumption (+0.003 LALs, 95% CI = 0.001 to 0.004, P = 0.006), but no significant change in off-premises beer per capita consumption. Second-wave restrictions (week beginning 06 July 2020) were associated with a significant immediate reduction in on-premises beer per capita consumption (-0.004 LALs, 95% CI = -0.006 to -0.002, P = 0.001) but, again, no significant change in off-premises beer per capita consumption.

CONCLUSION

Restricting the availability of on-premises alcohol during the first and second waves of the COVID-19 pandemic in Australia was associated with significant reductions in on-premises beer consumption, but no significant changes in off-premises beer consumption.

Effects of changes to the taxation of beer on alcohol consumption and government revenue in Australia

BACKGROUND

In 1988, the Australian government introduced a single nominal rate of tax on all beer products calculated on alcohol content. However, in 2000/01, varying nominal rates of tax were introduced for beer products according to three alcohol content levels (low-/mid-/high-strength) and container type (on-/off-premises). Little is known about the effect of the different tax policies on alcohol consumption and government revenue.

METHODS

We undertake time series analysis over 1989-2016 to examine the effect of beer tax policies in two sub-periods (before/after 2000/01) on category-level beer consumption per capita and government revenue. We also test if the policy changes in 2000/01 had immediate or long-term effects on total (all beer category) consumption over 1989-2016. Data includes monthly domestic beer sales volumes by category (in litres of alcohol), monthly government revenue from beer tax (AUD$), and inflation-adjusted tax rates (AUD$ per litre of alcohol).

RESULTS

Before 2000/01, the single nominal tax rate had a significant positive effect on revenue, but no significant effect on consumption. After 2000/01, the relatively higher nominal tax rates for two beer categories (mid- and high-strength off-premises) had a significant negative effect on their consumption, and a significant negative effect on revenue in one category (mid-strength off-premises). However, across the full period examined (1989-2016), the level and slope of total beer consumption was not significantly affected by the tax policy changes in 2000/01.

CONCLUSION

Raising alcohol taxes has the potential to reduce consumption and increase government revenue, but has been underutilised for these public health and public finance objectives in Australia.

Getting shops to voluntarily stop selling cheap, strong beers and ciders: a time-series analysis evaluating impacts on alcohol availability and purchasing

BACKGROUND

'Reducing the Strength' (RtS) is a public health initiative encouraging retailers to voluntarily stop selling cheap, strong beers/ciders (≥6.5% alcohol by volume). This study evaluates the impact of RtS initiatives on alcohol availability and purchasing in three English counties with a combined population of 3.62 million people.

METHODS

We used a multiple baseline time-series design to examine retail data over 29 months from a supermarket chain that experienced a two-wave, area-based role out of RtS: initially 54 stores (W1), then another 77 stores (W2). We measured impacts on units of alcohol sold (primary outcome: beers/ciders; secondary outcome: all alcoholic products), economic impacts on alcohol sales and substitution effects.

RESULTS

We observed a non-significant W1 increase (+3.7%, 95% CI: -11.2, 21.0) and W2 decrease (-6.8%, 95% CI: -20.5, 9.4) in the primary outcome. We observed a significant W2 decrease in units sold across all alcohol products (-10.5%, 95% CI: -19.2, -0.9). The direction of effect between waves was inconsistent for all outcomes, including alcohol sales, with no evidence of substitution effects.

CONCLUSIONS

In the UK, voluntary RtS initiatives appear to have little or no impact on reducing alcohol availability and purchase from the broader population of supermarket customers.

Alcohol consumption and future hospital usage: The EPIC-Norfolk prospective population study

BACKGROUND

Heavy drinkers of alcohol are reported to use hospitals more than non-drinkers, but it is unclear whether light-to-moderate drinkers use hospitals more than non-drinkers.

OBJECTIVE

We examined the relationship between alcohol consumption in 10,883 men and 12,857 women aged 40-79 years in the general population and subsequent admissions to hospital and time spent in hospital.

METHODS

Participants from the EPIC-Norfolk prospective population-based study were followed for ten years (1999-2009) using record linkage.

RESULTS

Compared to current non-drinkers, men who reported any alcohol drinking had a lower risk of spending more than twenty days in hospital multivariable adjusted OR 0.80 (95%CI 0.68-0.94) after adjusting for age, smoking status, education, social class, body mass index and prevalent diseases. Women who were current drinkers were less likely to have any hospital admissions multivariable adjusted OR 0.84 (95%CI 0.74-0.95), seven or more admissions OR 0.77 (95% CI 0.66-0.88) or more than twenty hospital days OR 0.70 (95%CI 0.62-0.80). However, compared to lifelong abstainers, men who were former drinkers had higher risk of any hospital admissions multivariable adjusted OR 2.22 (95%CI 1.51-3.28) and women former drinkers had higher risk of seven or more admissions OR 1.30 (95%CI 1.01-1.67).

CONCLUSION

Current alcohol consumption was associated with lower risk of future hospital usage compared with non-drinkers in this middle aged and older population. In men, this association may in part be due to whether former drinkers are included in the non-drinker reference group but in women, the association was consistent irrespective of the choice of reference group. In addition, there were few participants in this cohort with very high current alcohol intake. The measurement of past drinking, the separation of non-drinkers into former drinkers and lifelong abstainers and the choice of reference group are all influential in interpreting the risk of alcohol consumption on future hospitalisation.

Population cigarette consumption in Great Britain: novel insights using retail sales data

Background

Accurate data to measure population cigarette consumption are vital for surveillance and for evaluating the impact of tobacco control policies. This study uses cigarette retail sales data to provide novel insights into trends and patterns in cigarette consumption in Great Britain.

Methods

Cigarette sales estimates derived from electronic sales from most large grocery stores and a weighted representative sample of smaller convenience stores were obtained from Nielsen. Data on the number of cigarette sticks sold per calendar month and per week were obtained for Scotland and England/Wales (combined) for the period January 2008 to December 2015. Cigarette consumption per adult smoker per month was calculated using survey-based smoking prevalence estimates and mid-year population estimates.

Results

Population cigarette consumption in Great Britain declined between 2008 and 2013. Cigarette sales have since stabilised at around 400 cigarettes per adult smoker per month. Cigarettes sold in 14- to 19-packs have substituted a sharp decline in 20-packs and now account for over half of all cigarettes sold in Great Britain. Cigarette consumption has been consistently higher in Scotland than England/Wales. This is due to higher sales of 20-packs in Scotland between 2008 and 2013, which has been substituted by higher sales of 14- to 19-packs in recent years.

Conclusions

Cigarette retail sales data provide unique insights into levels and patterns of cigarette consumption and should be used for monitoring and evaluating tobacco control policy in Great Britain.

Electronic supplementary material

The online version of this article (10.1186/s12889-017-4950-z) contains supplementary material, which is available to authorized users.

Adjustment for survey non-representativeness using record-linkage: refined estimates of alcohol consumption by deprivation in Scotland

BACKGROUND AND AIMS

Analytical approaches to addressing survey non-participation bias typically use only demographic information to improve estimates. We applied a novel methodology which uses health information from data linkage to adjust for non-representativeness. We illustrate the method by presenting adjusted alcohol consumption estimates for Scotland.

DESIGN

Data on consenting respondents to the Scottish Health Surveys (SHeSs) 1995-2010 were linked confidentially to routinely collected hospital admission and mortality records. Synthetic observations representing non-respondents were created using general population data. Multiple imputation was performed to compute adjusted alcohol estimates given a range of assumptions about the missing data. Adjusted estimates of mean weekly consumption were additionally calibrated to per-capita alcohol sales data.

SETTING

Scotland.

PARTICIPANTS

13 936 male and 18 021 female respondents to the SHeSs 1995-2010, aged 20-64 years.

MEASUREMENTS

Weekly alcohol consumption, non-, binge- and problem-drinking.

FINDINGS

Initial adjustment for non-response resulted in estimates of mean weekly consumption that were elevated by up to 17.8% [26.5 units (18.6-34.4)] compared with corrections based solely on socio-demographic data [22.5 (17.7-27.3)]; other drinking behaviour estimates were little changed. Under more extreme assumptions the overall difference was up to 53%, and calibrating to sales estimates resulted in up to 88% difference. Increases were especially pronounced among males in deprived areas.

CONCLUSIONS

The use of routinely collected health data to reduce bias arising from survey non-response resulted in higher alcohol consumption estimates among working-age males in Scotland, with less impact for females. This new method of bias reduction can be generalized to other surveys to improve estimates of alternative harmful behaviours.

Informing Investment to Reduce Inequalities: A Modelling Approach

Background

Reducing health inequalities is an important policy objective but there is limited quantitative information about the impact of specific interventions.

Objectives

To provide estimates of the impact of a range of interventions on health and health inequalities.

Materials and Methods

Literature reviews were conducted to identify the best evidence linking interventions to mortality and hospital admissions. We examined interventions across the determinants of health: a ‘living wage’; changes to benefits, taxation and employment; active travel; tobacco taxation; smoking cessation, alcohol brief interventions, and weight management services. A model was developed to estimate mortality and years of life lost (YLL) in intervention and comparison populations over a 20-year time period following interventions delivered only in the first year. We estimated changes in inequalities using the relative index of inequality (RII).

Results

Introduction of a ‘living wage’ generated the largest beneficial health impact, with modest reductions in health inequalities. Benefits increases had modest positive impacts on health and health inequalities. Income tax increases had negative impacts on population health but reduced inequalities, while council tax increases worsened both health and health inequalities. Active travel increases had minimally positive effects on population health but widened health inequalities. Increases in employment reduced inequalities only when targeted to the most deprived groups. Tobacco taxation had modestly positive impacts on health but little impact on health inequalities. Alcohol brief interventions had modestly positive impacts on health and health inequalities only when strongly socially targeted, while smoking cessation and weight-reduction programmes had minimal impacts on health and health inequalities even when socially targeted.

Conclusions

Interventions have markedly different effects on mortality, hospitalisations and inequalities. The most effective (and likely cost-effective) interventions for reducing inequalities were regulatory and tax options. Interventions focused on individual agency were much less likely to impact on inequalities, even when targeted at the most deprived communities.

Estimating average alcohol consumption in the population using multiple sources: the case of Spain

Background

National estimates on per capita alcohol consumption are provided regularly by various sources and may have validity problems, so corrections are needed for monitoring and assessment purposes. Our objectives were to compare different alcohol availability estimates for Spain, to build the best estimate (actual consumption), characterize its time trend during 2001–2011, and quantify the extent to which other estimates (coverage) approximated actual consumption.

Methods

Estimates were: alcohol availability from the Spanish Tax Agency (Tax Agency availability), World Health Organization (WHO availability) and other international agencies, self-reported purchases from the Spanish Food Consumption Panel, and self-reported consumption from population surveys. Analyses included calculating: between-agency discrepancy in availability, multisource availability (correcting Tax Agency availability by underestimation of wine and cider), actual consumption (adjusting multisource availability by unrecorded alcohol consumption/purchases and alcohol losses), and coverage of selected estimates. Sensitivity analyses were undertaken. Time trends were characterized by joinpoint regression.

Results

Between-agency discrepancy in alcohol availability remained high in 2011, mainly because of wine and spirits, although some decrease was observed during the study period.

The actual consumption was 9.5 l of pure alcohol/person-year in 2011, decreasing 2.3 % annually, mainly due to wine and spirits. 2011 coverage of WHO availability, Tax Agency availability, self-reported purchases, and self-reported consumption was 99.5, 99.5, 66.3, and 28.0 %, respectively, generally with downward trends (last three estimates, especially self-reported consumption). The multisource availability overestimated actual consumption by 12.3 %, mainly due to tourism imbalance.

Conclusions

Spanish estimates of per capita alcohol consumption show considerable weaknesses. Using uncorrected estimates, especially self-reported consumption, for monitoring or other purposes is misleading. To obtain conservative estimates of alcohol-attributable disease burden or heavy drinking prevalence, self-reported consumption should be shifted upwards by more than 85 % (91 % in 2011) of Tax Agency or WHO availability figures. The weaknesses identified can probably also be found worldwide, thus much empirical work remains to be done to improve estimates of per capita alcohol consumption.

Electronic supplementary material

The online version of this article (doi:10.1186/s12963-016-0090-4) contains supplementary material, which is available to authorized users.

Tracking Biases: An Update to the Validity and Reliability of Alcohol Retail Sales Data for Estimating Population Consumption in Scotland

AIMS

To highlight the importance of monitoring biases when using retail sales data to estimate population alcohol consumption.

METHODS

Previously, we identified and where possible quantified sources of bias that may lead to under- or overestimation of alcohol consumption in Scotland. Here, we update findings by using more recent data and by quantifying emergent biases.

RESULTS

Underestimation resulting from the net effect of biases on population consumption in Scotland increased from -4% in 2010 to -7% in 2013.

CONCLUSION

Biases that might impact on the validity and reliability of sales data when estimating population consumption should be routinely monitored and updated.

Regional alcohol consumption and alcohol-related mortality in Great Britain: novel insights using retail sales data

Background

Regional differences in population levels of alcohol-related harm exist across Great Britain, but these are not entirely consistent with differences in population levels of alcohol consumption. This incongruence may be due to the use of self-report surveys to estimate consumption. Survey data are subject to various biases and typically produce consumption estimates much lower than those based on objective alcohol sales data. However, sales data have never been used to estimate regional consumption within Great Britain (GB). This ecological study uses alcohol retail sales data to provide novel insights into regional alcohol consumption in GB, and to explore the relationship between alcohol consumption and alcohol-related mortality.

Methods

Alcohol sales estimates derived from electronic sales, delivery records and retail outlet sampling were obtained. The volume of pure alcohol sold was used to estimate per adult consumption, by market sector and drink type, across eleven GB regions in 2010–11. Alcohol-related mortality rates were calculated for the same regions and a cross-sectional correlation analysis between consumption and mortality was performed.

Results

Per adult consumption in northern England was above the GB average and characterised by high beer sales. A high level of consumption in South West England was driven by on-trade sales of cider and spirits and off-trade wine sales. Scottish regions had substantially higher spirits sales than elsewhere in GB, particularly through the off-trade. London had the lowest per adult consumption, attributable to lower off-trade sales across most drink types. Alcohol-related mortality was generally higher in regions with higher per adult consumption. The relationship was weakened by the South West and Central Scotland regions, which had the highest consumption levels, but discordantly low and very high alcohol-related mortality rates, respectively.

Conclusions

This study provides support for the ecological relationship between alcohol-related mortality and alcohol consumption. The synthesis of knowledge from a combination of sales, survey and mortality data, as well as primary research studies, is key to ensuring that regional alcohol consumption, and its relationship with alcohol-related harms, is better understood.

Evaluating the impact of the alcohol act on off-trade alcohol sales: a natural experiment in Scotland

BACKGROUND AND AIMS

A ban on multi-buy discounts of off-trade alcohol was introduced as part of the Alcohol Act in Scotland in October 2011. The aim of this study was to assess the impact of this legislation on alcohol sales, which provide the best indicator of population consumption.

DESIGN, SETTING AND PARTICIPANTS

Interrupted time-series regression was used to assess the impact of the Alcohol Act on alcohol sales among off-trade retailers in Scotland. Models accounted for underlying seasonal and secular trends and were adjusted for disposable income, alcohol prices and substitution effects. Data for off-trade retailers in England and Wales combined (EW) provided a control group.

MEASUREMENTS

Weekly data on the volume of pure alcohol sold by off-trade retailers in Scotland and EW between January 2009 and September 2012.

FINDINGS

The introduction of the legislation was associated with a 2.6% (95% CI = -5.3 to 0.2%, P = 0.07) decrease in off-trade alcohol sales in Scotland, but not in EW (-0.5%, 95% CI = -4.6 to 3.9%, P = 0.83). A statistically significant reduction was observed in Scotland when EW sales were adjusted for in the analysis (-1.7%, 95% CI = -3.1 to -0.3%, P = 0.02). The decline in Scotland was driven by reduced off-trade sales of wine (-4.0%, 95% CI = -5.4 to -2.6%, P < 0.001) and pre-mixed beverages (-8.5%, 95% CI = -12.7 to -4.1%, P < 0.001). There were no associated changes in other drink types in Scotland, or in sales of any drink type in EW.

CONCLUSIONS

The introduction of the Alcohol Act in Scotland in 2011 was associated with a decrease in total off-trade alcohol sales in Scotland, largely driven by reduced off-trade wine sales.

Minimum pricing of alcohol versus volumetric taxation: which policy will reduce heavy consumption without adversely affecting light and moderate consumers?

BACKGROUND

We estimate the effect on light, moderate and heavy consumers of alcohol from implementing a minimum unit price for alcohol (MUP) compared with a uniform volumetric tax.

METHODS

We analyse scanner data from a panel survey of demographically representative households (n = 885) collected over a one-year period (24 Jan 2010-22 Jan 2011) in the state of Victoria, Australia, which includes detailed records of each household's off-trade alcohol purchasing.

FINDINGS

The heaviest consumers (3% of the sample) currently purchase 20% of the total litres of alcohol (LALs), are more likely to purchase cask wine and full strength beer, and pay significantly less on average per standard drink compared to the lightest consumers (A$1.31 [95% CI 1.20-1.41] compared to $2.21 [95% CI 2.10-2.31]). Applying a MUP of A$1 per standard drink has a greater effect on reducing the mean annual volume of alcohol purchased by the heaviest consumers of wine (15.78 LALs [95% CI 14.86-16.69]) and beer (1.85 LALs [95% CI 1.64-2.05]) compared to a uniform volumetric tax (9.56 LALs [95% CI 9.10-10.01] and 0.49 LALs [95% CI 0.46-0.41], respectively). A MUP results in smaller increases in the annual cost for the heaviest consumers of wine ($393.60 [95% CI 374.19-413.00]) and beer ($108.26 [95% CI 94.76-121.75]), compared to a uniform volumetric tax ($552.46 [95% CI 530.55-574.36] and $163.92 [95% CI 152.79-175.03], respectively). Both a MUP and uniform volumetric tax have little effect on changing the annual cost of wine and beer for light and moderate consumers, and likewise little effect upon their purchasing.

CONCLUSIONS

While both a MUP and a uniform volumetric tax have potential to reduce heavy consumption of wine and beer without adversely affecting light and moderate consumers, a MUP offers the potential to achieve greater reductions in heavy consumption at a lower overall annual cost to consumers.

Use of record-linkage to handle non-response and improve alcohol consumption estimates in health survey data: a study protocol

INTRODUCTION

Reliable estimates of health-related behaviours, such as levels of alcohol consumption in the population, are required to formulate and evaluate policies. National surveys provide such data; validity depends on generalisability, but this is threatened by declining response levels. Attempts to address bias arising from non-response are typically limited to survey weights based on sociodemographic characteristics, which do not capture differential health and related behaviours within categories. This project aims to explore and address non-response bias in health surveys with a focus on alcohol consumption.

METHODS AND ANALYSIS

The Scottish Health Surveys (SHeS) aim to provide estimates representative of the Scottish population living in private households. Survey data of consenting participants (92% of the achieved sample) have been record-linked to routine hospital admission (Scottish Morbidity Records (SMR)) and mortality (from National Records of Scotland (NRS)) data for surveys conducted in 1995, 1998, 2003, 2008, 2009 and 2010 (total adult sample size around 40 000), with maximum follow-up of 16 years. Also available are census information and SMR/NRS data for the general population. Comparisons of alcohol-related mortality and hospital admission rates in the linked SHeS-SMR/NRS with those in the general population will be made. Survey data will be augmented by quantification of differences to refine alcohol consumption estimates through the application of multiple imputation or inverse probability weighting. The resulting corrected estimates of population alcohol consumption will enable superior policy evaluation. An advanced weighting procedure will be developed for wider use.

ETHICS AND DISSEMINATION

Ethics approval for SHeS has been given by the National Health Service (NHS) Multi-Centre Research Ethics Committee and use of linked data has been approved by the Privacy Advisory Committee to the Board of NHS National Services Scotland and Registrar General. Funding has been granted by the MRC. The outputs will include four or five public health and statistical methodological international journal and conference papers.

PRIMARY SUBJECT HEADING

Public health.

SECONDARY SUBJECT HEADING

Addiction: health policy; mental health.

A review of the validity and reliability of alcohol retail sales data for monitoring population levels of alcohol consumption: a Scottish perspective

AIMS

To assess the validity and reliability of using alcohol retail sales data to measure and monitor population levels of alcohol consumption.

METHODS

Potential sources of bias that could lead to under- or overestimation of population alcohol consumption based on alcohol retail sales data were identified and, where possible, quantified. This enabled an assessment of the potential impact of each bias on alcohol consumption estimates in Scotland.

RESULTS

Overall, considering all the possible sources of overestimation and underestimation, and taking into account the potential for sampling variability to impact on the results, the range of uncertainty of consumption during 2010 was from an overestimate of 0.3 l to an underestimate of 2.4 l of pure alcohol per adult. This excludes the impacts of alcohol stockpiling and alcohol sold through outlets not included in the sampling frame. On balance, there is therefore far greater scope for alcohol retail sales data to be underestimating per adult alcohol consumption in Scotland than there is for overestimation.

CONCLUSION

Alcohol retail sales data offer a robust source of data for monitoring per adult alcohol consumption in Scotland. Consideration of the sources of bias and a comprehensive understanding of data collection methods are essential for using sales data to monitor trends in alcohol consumption.