Drop-out from addiction treatment: a systematic review of risk factors.

Completion of addiction treatment is one of the most consistent factors associated with a favorable treatment outcome. Unfortunately, it is more common for a patient to drop-out of addiction treatment than to complete the treatment. To prevent drop-out, risk factors must be identified. This box-score review focuses on studies investigating the risk factors associated with drop-out from addiction treatment published in peer-reviewed journals from 1992 to 2013. A total of 122 studies involving 199,331 participants met the inclusion criteria. Contrary to recommendations from previous reviews, 91% of the included studies focused primarily on enduring patient factors, mainly demographics. The most consistent risk factors across the different study designs, samples, and measurement methods were cognitive deficits, low treatment alliance, personality disorder, and younger age. With the exception of younger age, none of the demographic factors emerged as consistent risk factors. Further research on the relationship between simple demographic factors and drop-out risk is of limited value. However, little is known about the potential risk factors related to treatment programs and to the treatment processes. Based on the review, clinical recommendations include assessing cognitive functioning and personality disorders at baseline and continuous monitoring of treatment alliance.