Cochrane systematic reviews in the field of addiction: past and future.

The Cochrane Drugs and Alcohol Group aims to produce, update, and disseminate systematic reviews on the prevention, treatment, and rehabilitation of problematic drug and alcohol use. This paper describes what the Group has done since the 1990s to produce evidence to guide policy, practice, and research.We analyze the coverage of topics by our reviews, the body of studies they have included, and the evidence produced.By July 2013, the Group had published 67 reviews, with 376 authors from 25 different countries. These reviews included 906 studies, of 3061 studies considered for inclusion. Most (90\%) included studies were randomized trials. Considering the 'Implications for practice' section of each review, 41\% interventions were classified as 'do it', 15\% as 'do not do', and 44\% as 'do only in research'. These proportions varied according to the type of substance of abuse studied. The proportion of 'do it' interventions were 46\% for alcohol, 40\% for opioids, 20\% for psychostimulants, 40\% for polydrugs, and 62\% for prevention.Cochrane Reviews produced by the Drugs and Alcohol Group provide evidence on the effectiveness of several interventions, and identify areas of uncertainty where new research is needed.