An adaptation of the Yesterday Method to correct for under-reporting of alcohol consumption and estimate compliance with Canadian low-risk drinking guidelines.

objectivesTo estimate compliance with Canada's Low-Risk Alcohol Drinking Guidelines (LRDG) in different groups of drinkers after adjusting for underreporting of alcohol use, and to identify which types of beverage are more likely to be consumed when LRDGs are exceeded.

methodOur sample consisted of 43,242 Canadians aged 15 and over who had responded to the Canadian Alcohol and Drug Use Monitoring Survey, 2008-2010. Consumption in excess of LRDG was estimated for subgroups of drinkers after adjustment for under-reporting of consumption. Responses to Beverage-Specific Yesterday questions were used to make age-, gender- and beverage-specific corrections to under-reporting for data from the last 12 months Quantity-Frequency questions. Statistics Canada data on sales of beer, wine and spirits were also incorporated into the adjusted calculations.

resultsAfter adjustment for under-reporting, non-compliance with weekly LRDG limits to reduce risk of long-term harm increased from 6.8% to 27.3% among drinkers, and from 42.3% to 68.3% with respect to drinks. Non-compliance with daily LRDG limits to reduce risk of short-term harm increased from 16.7% to 38.6% among drinkers, and from 53.3% to 80.5% with respect to drinks. After adjustment, over 92% of total consumption occurred on risky drinking days among underage Canadians and over 91% of consumption reported by young adults took place during risky drinking occasions. Wine was least likely to be drunk in a risky fashion, spirits were the most likely.

conclusionWhen corrections for under-reporting are made, most Canadian alcohol consumption occurs on days when national LRDG are exceeded, especially for underage and young adult drinkers.