Stockwell and his team in Canada has published a new study in the March 2016 issue of the Journal of Studies on Alcohol and Drugs, "Do "Moderate" Drinkers Have Reduced Mortality Risk? A Systematic Review and Meta-Analysis of Alcohol Consumption and All-Cause Mortality."
The new study was a systematic review and meta-regression analysis of studies investigating alcohol use and mortality risk after controlling for quality-related study characteristics was conducted in a population of 3,998,626 individuals, among whom 367,103 deaths were recorded. A total of 87 studies were examined.
Tim Stockwell, Ph.D., the lead researcher on the analysis and director of the University of Victoria's Centre for Addictions Research in British Columbia, Canada said that "Most often, studies have compared moderate drinkers (people who have up to two drinks per day) with "current" abstainers. The problem is that this abstainer group can include people in poor health who've cut out alcohol. A fundamental question is, who are these moderate drinkers being compared against?"
The paper concluded that when his team corrected for those abstainer "biases" and certain other study-design issues, moderate drinkers no longer showed a longevity advantage. Further, only 13 of the 87 studies avoided biasing the abstainer comparison group--and these showed no health benefits. It stated that "Estimates of mortality risk from alcohol are significantly altered by study design and characteristics. Meta-analyses adjusting for these factors find that low-volume alcohol consumption has no net mortality benefit compared with lifetime abstention or occasional drinking. These findings have implications for public policy, the formulation of low-risk drinking guidelines, and future research on alcohol and health."
Stockwell's dismissive attitude to many previous studies citing these study biases and poor design is not universally accepted. Some academics saying that his team's negative opinion of clinical studies with a positive association of moderate drinking with alcohol is an over zealous attempt to portray a prohibitionist stance to alcohol. Given that Stockwell is based at the University of Victoria's Centre for Addictions Research in British Columbia, the title of the department may give underlying motivations away when it comes to funding and the desired outcome to be sceptical of any positive benefits of alcohol or wine.