Cochrane systematic reviews in the field of addiction: what's there and what should be.

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. The objective of the present paper was to summarize the main characteristics of the published systematic reviews in the field of drug and alcohol dependence, in terms of the topics covered, methods used to produce the reviews, and available evidence. By January 2010, the Group had published 52 reviews with 694 primary studies included out of 2059 studies considered for inclusion. Of these publications, 44% were published in 12 journals, including Drug and Alcohol Dependence (11%) with the highest number of publications, and 68% were conducted in North America. The majority of included studies (90%) were randomized controlled trials. Evaluating their methodological quality, we found that allocation concealment methods were not properly described in the majority of studies (18% adequate, 73% unclear, 9% inadequate). The percentage of interventions shown to be beneficial varied according to the substance considered: 42% for opioids, 37% for alcohol, 14% for psychostimulants, 7% for polydrugs, and 33% for prevention. Furthermore, 75% of the reviews provided specific information on further research needs. Cochrane reviews provide information on the most effective treatments, particularly in the area of opioid and alcohol dependence, and help clarify areas for further research.