Treatment of internet addiction: a meta-analysis.

Internet addiction (IA) has become a widespread and problematic phenomenon. Little is known about the efficacy of treatment approaches for IA. Therefore, our objective was to perform an effect size analysis of psychological and pharmacological interventions for IA. We conducted a literature search using PsycINFO, PSYNDEX, MEDLINE, EMBASE, PQDT OPEN, WorldCat, Cochrane Clinical Trials Library, and manual searches. Our meta-analysis was based on 16 studies, covered a total of 670 participants, and used a random effects model. Special emphasis was given to the inclusion of studies from "non-western" countries. Effect size estimates suggest that psychological and pharmacological interventions were highly effective for improving IA (g=1.61), time spent online (g=0.94), depression (g=0.90) and anxiety (g=1.25) from pre- to post-treatment in the overall sample. Moderator analyses revealed that studies including individual treatments, a higher number of female participants, older patients, or a North-American sample had larger effect sizes for some outcome variables. Most effect sizes were high, robust, unrelated to study quality or design, and maintained over follow-up. Due to a small number of included studies and methodological limitations the results of this meta-analysis should be regarded as preliminary.