A meta-analysis of the relationship between trait mindfulness and substance use behaviors.

BACKGROUND The relationship between trait mindfulness and substance use behaviors has been inconsistent across studies. The current meta-analysis aimed at quantifying the magnitude of this relationship, and at determining how this relationship varies in context of (1) mindfulness facets, (2) substance type, (3) sample characteristics, and (4) substance use severity. METHODS Using electronic databases, the literature search yielded 303 articles, but only 39 articles met inclusion criteria to be included in this meta-analysis. The relationship was quantified as a Pearson's r correlation coefficient for all studies. RESULTS Findings indicated a small, negative, and significant trait mindfulness-substance use behaviors relationship (r=-0.13). This relationship varied across substance type, clinical status of the sample, and substance use severity. Mindfulness facet was not a significant moderator; however, only particular facets (e.g., acting with awareness, non-judgment, and non-reactivity) were consistently associated with substance use behaviors. CONCLUSIONS This meta-analysis quantified the trait mindfulness-substance use behaviors relationship, which can be used as future effect size estimates. Findings also indicated that the trait mindfulness-substance use behaviors relationship was more robust: (1) for alcohol and tobacco use compared to marijuana use behaviors; (2) for problematic compared to non-problematic substance use behaviors; and (3) with inpatient compared to outpatient and non-clinical samples. Further work should continue to examine if acting with awareness, non-judgment, and non-reactivity mindfulness facets are more robustly associated with substance use behaviors. Failure to consider these factors, or collapsing across these factors, could explain the smaller or inconsistently reported associations across previous studies.