Alcohol and drug treatment outcome studies: new methodological review (2005–2010) and comparison with past reviews

• The current review evaluates the methodological rigor of alcohol and drug studies.
• The current review examines changes over time in reporting of key study variables.
• A greater proportion of studies utilized continuous assessment measures.
• More studies are using problem severity measures than found in previous reviews.
• Areas for improvement are identified, including the reporting of demographic data.

ObjectiveSeveral methodological reviews of alcohol treatment outcome studies and one review of drug studies have been published over the past 40 years. Although past reviews demonstrated methodological improvements in alcohol studies, they also found continued deficiencies. The current review allows for an updated evaluation of the methodological rigor of alcohol and drug studies and, by utilizing inclusion criteria similar to previous reviews, it allows for a comparative review over time. In addition, this is the first review that compares the methodology of alcohol and drug treatment outcome studies published during the same time period.MethodThe methodology for 25 alcohol and 11 drug treatment outcome studies published from 2005 through 2010 that met the review's inclusion criteria was evaluated. The majority of variables evaluated were used in prior reviews.ResultsThe current review found that more alcohol and drug treatment outcome studies are now using continuous substance use measures and assessing problem severity. Although there have been methodological improvements over time, the current reviews differed little from their most recent past counterpart. Despite this finding, some areas, particularly the continued low reporting of demographic data, needs strengthening.ConclusionsImprovement in the methodological rigor of alcohol and drug treatment outcome studies has occurred over time. The current review found few differences between alcohol and drug study methodologies as well as few differences between the current review and the most recent past alcohol and drug reviews.