Alcohol consumption: Methodology

The alcohol consumption component of the BC alcohol and other drug (AOD) monitoring project (now housed under Co/Lab) assembles time-series data on alcohol sales in different geographic regions of British Columbia. Such data can be used to better understand epidemiological issues related to alcohol consumption, policy development, evaluation and interventions.

Key findings from this component can be found in facts & stats/alcohol consumption in BC.

Our interactive trend analyzer allows you to explore and compare the impacts and statistical trends of alcohol, tobacco, and other drug use for different groups of people in different parts of BC, including maps of alcohol consumption. 

Methodology

This report presents the estimates of per capita litres of absolute alcohol consumption and rates of outlet per 100,000 adults aged 15+ for 89 local health areas (LHAs), 16 health service delivery areas (HSDAs), 5 health authorities (HAs) and the whole province in the province of British Columbia (BC) of Canada during the period from 2002 to 2022 (calendar years 2002-2022 and fiscal year 2002/03-2022/23) based on the alcohol sale data and the Ubrew/Uvin data obtained from the BC Liquor Distribution Branch (BCLDB) and the Liquor Control and Licensing Branch (now the Liquor and Cannabis Regulation Branch).

1. Methods

1.1. Alcohol sales data

The estimates of total absolute alcohol consumption for health regions in BC in this report were based on two data sources, the sale alcohol data from the BCLDB and the Ubrew/Uvin data from the BC Liquor Control and Licensing Branch. Both of these branches report to the Ministry of Finance.

1.1.1. Sale data

The BC alcohol sales data were obtained from the BCLDB which regulates the distribution, importation and retailing of beverage alcohol in BC and operates nearly 200 government liquor stores in the province. The data were collapsed by the BCLDB into 89 BC local health areas (LHAs) and into 4 or 5 week periods for the fiscal years from 2002/03 to 2018/19. The weekly sales data were requested for the period from April 2019 to the first week of April 2023.

The health structure file was used to merge alcohol consumption data by LHA into HSDAs and HAs in order to estimate alcohol consumption for LHAs, HSDAs and HAs.

The data included the litres of absolute alcohol sold at off-site government (GLS) and private liquor stores (PLS), and on-premise establishments (restaurant and bar) for the fiscal years 2002/03-2022/23. Alcohol sales were broken down by type of beverage (beer, cooler, spirit and wine), and within each beverage type, with groupings based on the percent of alcohol for each product. The number of establishments by take-out premises (take-out government liquor stores and private liquor stores) and two categories of on-premise (restaurant and bar) sales were also included.

1.1.2. Ubrew and Uvin data

U-Brew and U-Vin data were obtained from the Liquor Control and Licensing Branch (LCLB, now the Liquor and Cannabis Regulation Branch) which issues licenses in BC for making and selling liquor and supervises the service of liquor in licensed establishments. The data in litres of beverage volumes for beers, coolers/ciders and wines in fiscal years 2002/03-2005/06 (April 2002 to December 2006) were provided for municipalities by the LCLB. The Ubrew and Uvin data for fiscal years 2007/08-2022/23 were unavailable, and extrapolations were used for estimates. The beers, coolers/ciders and wines in beverage volume in litres from Ubrew and Uvin were provided and conversion factors for these beverages were used to convert the beverages to absolute alcohol consumption in litres. The volume of absolute alcohol from Ubrew/Uvin production was calculated with conversion factors of 5.04% for beer and 6.77% for ciders, and 12.53% for wines.1

1.2. Alcohol outlet data

As the sales data, the outlet data were also received from the BCLDB. The data were collapsed by the BCLDB into 89 BC local health areas (LHAs) and into 4 or 5 week periods for the fiscal years from 2002/03 to 2022/23. The outlets included active counts of restaurants, bars, GLSs and PLSs in 12 periods in each fiscal year. The health structure file was used to merge the outlet data by LHAs into HSDAs and HAs in order to estimate annual outlet density for LHAs, HSDAs and HAs. We calculated annual counts of total outlets, restaurants, bars, GLS, and PLSs per 100,000 adults aged 15+ in 89 LHAs, 16 HSDAs, 5 HAs and BC for fiscal years 2002/03 to 2022/23 and calendar years 2002-2022 by dividing annual populations aged 15 years or older; we also calculated adjusted counts of outlets for fiscal and calendar years adjusting for various number of days in fiscal periods (months).

1.3. Population data

Provincial population data, classified into 89 LHAs were obtained from BC STATS.2 The data set consists of population estimates for years 1986-2041 which incorporate information from the 1986, 1991, 1996, 2001, 2006 and 2011 Censuses of Canada. BC Stats produces sub-provincial population estimates using the Generalized Estimates System (GES) on an annual basis. These sub-provincial population estimates are based on the 2011 Census counts adjusted for census net undercoverage and incompletely enumerated Indian Reserves to which is added the estimated demographic growth for the period from May 10, 2011, to July 1, 2016. More details on methodology can be found elsewhere.3 The Spline method 4 was used to estimate the monthly and fiscal period populations aged 15 years or older in each LHA for the project period. The data were updated by BC STATS in April 2023. The PCA and outlet density estimates were based on the updated population.

1.4. Statistical analyses

 There are a total of 89 LHAs nested within 16 HSDAs within 5 HAs in BC. Per capita alcohol consumption for all these health areas from calendar years 2002 to 2021 and fiscal years 2002/03 to 2021/22 was estimated by taking total absolute alcohol consumption, and by types of outlets (restaurant, bar, GLS, PLS or Ubrew) and beverages (beer, cooler, spirit or wine) in each year and dividing it by population aged 15 years old and over in each area.5 The alcohol consumption for years 2002 and the first three months of 2003 was estimated based on total alcohol consumption for each LHA by month and the proportion of alcohol consumption in each LHA by month in years 2004-2011. The alcohol and population data for LHAs in each fiscal or calendar year within each HSDA and HA were aggregated to estimate PCA for HSDAs and HAs each year. Because this estimate procedure of the consumption for years 2002-2022 has been changed and the updated population dataset from the BC STATS was used, the PCA for some areas has been changed slightly compared to the estimate last year. The estimates of PCA in some years for Nisga’a and Telegraph Creek have been suppressed because of low estimates of the consumption and small number of outlets.

Dollars per drink were calculated for the whole province for calendar years 2002-2022 and fiscal years 2002/03 – 2022/23. The estimates were done by outlet (restaurant, bar, government liquor store, and private liquor store) and beverage (beer, cooler, spirit and wine) types for calendar years 2002-2022 and fiscal years 2002/03-2022/23.

Per capita low priced alcohol consumption ($1.14 per drink=17.05 or $66.67 per litre ethanol) was also estimated for the province in calendar years 2002-2022 and fiscal years 2002/03-2022/23.

Calendar and fiscal year counts of outlet per 100,000 population aged 15+ for all the health areas were calculated by using counts of all outlets and by types of outlet (restaurants, bars, GLSs and PLSs) divided by calendar year/fiscal year population aged 15+. Calendar month and fiscal period counts of outlet per 100,000 population aged 15+ for all the health areas were also calculated by using period counts of all outlets (period mean counts) and by types of outlet (restaurants, bars, GLSs and PLSs) divided by calendar month/fiscal period population aged 15+.

The estimates of either PCA or outlet rates in LHA Nisga’a and Telegraph Creek have been suppressed because the estimates based on small amount of the sales data and counts of outlet are unreliable.

References

  1. alcohol consumption in British Columbia using alcohol sales data: A foundation for public health monitoring. Contemporary Drug Problems 2009; 36(Fall/Winter): 18.

  2. BC Stats. P.E.O.P.L.E. 2020 Population Projections. August 2017 ed: BC Stats. Available from URL: https://bcstats.shinyapps.io/popProjApp/. Accessible 31 November 2022; 2022.

  3. BC Stats Population Section. P.E.O.P.L.E. Methodology: Population extrapolation for organizational planning with less error. Accessible on Sugust 31, 2018: https://www2.gov.bc.ca/gov/content/data/statistics/people-population-community/population/population-projections. Victoria, BC, 1999.

  4. Mcneil DR, Trussell TJ, Turner JC. Spline Interpolation of Demographic Data. Demography 1977; 14(2): 245-52.

  5. Stockwell T, Chikritzhs T. International guide for monitoring alcohol consumption and related harm. Geneva: World Health Organization. Available from URL: https://www.who.int/publications/i/item/international-guide-for-monitoring-alcohol-consumption-and-related-harm. Accessible 31 December 2022; 2000.

Team

Dr. Adam Sherk
Dr. Tim Stockwell 
Dr. Jinhui Zhao