This study presents the first systematic review and meta-analysis examining the associations between the HEXACO personality traits, substance use disorders (SUDs), and behavioral addictions.

A comprehensive search was conducted on the databases APA PsycINFO (Ovid), Medline (Ovid), ProQuest, Web of Science, CINAHL, and Wiley Online Library, with a supplementary search on Google Scholar. Studies were included if they were empirical, published in peer-reviewed journals or as dissertations, investigated the association between HEXACO personality traits, SUDs, and behavioral addictions, and reported zero-order correlations or sufficient data for such calculations. Case studies and qualitative studies were excluded. Two reviewers independently screened studies, extracted data, and assessed risk of bias using the Newcastle-Ottawa Scale. Random effects models were used to estimate pooled effect sizes for behavioral addictions. For SUD analyses, fixed effects model was applied as only two studies were available per trait.

Nineteen studies with a total of 9,478 participants were included. Meta-analytic results showed statistically significant inverse associations between behavioral addictions and honesty-humility (−0.339, 95 % CI = −0.433, −0.237), extraversion (−0.197, 95 % CI = −0.321, −0.066), agreeableness (−0.336, 95 % CI = −0.478, −0.177), conscientiousness (−0.317, 95 % CI = −0.410, −0.218), and openness to experience (−0.201, 95 % CI = −0.322, −0.073), while emotionality showed a statistically significant positive association (0.212, 95 % CI = 0.094, 0.324). For SUDs, analyses demonstrated statistically significant inverse associations with honesty-humility (−0.226, 95 % CI = −0.298, −0.150) and conscientiousness (−0.157, 95 % CI = −0.232, −0.081), while other traits showed non-significant associations. Significant heterogeneity was observed across studies. Meta-regressions showed that gender and age moderated the relationship between agreeableness and behavioral addictions, while gender also moderated the relationship between extraversion and behavioral addictions.

This meta-analysis provides strong empirical evidence for an association between HEXACO personality traits and addictions. The findings suggest that incorporating HEXACO trait assessments may be beneficial in planning and targeting interventions for individuals with addictions, but that the population in question also should be taken into account.