Efficacy of internet-based psychological interventions for pathological health anxiety: A three-level meta-analysis of randomized controlled trials

Objective: This study aimed to provide a comprehensive summary and synthesis of available evidence on the efficacy of internet-based psychological interventions for pathological health anxiety, as well as to examine the variables that possibly moderate intervention effects. Method: Four databases were searched for the literature up to October 2023. A three-level random-effects model was used to estimate the pooled effect size, with Hedge's g as the measure. Results: We extracted 28 effect sizes from nine eligible randomized controlled trials with 1079 participants. The results showed that internet-based psychological interventions had a moderate to large between-group effect on health anxiety (g = 0.70) that was significant both at post-intervention (g = 0.74) and follow-up (g = 0.64). Furthermore, these interventions were significantly more effective than passive control conditions including waitlist, usual care, and placebo at post-treatment (g =1.07), but had effects comparable to active control groups at both post-intervention and follow-up. Conclusions: Internet-based psychological interventions are an effective way to alleviate pathological health anxiety. We recommend that these interventions be more widely implemented in routine care settings to ensure easy accessibility for patients with health anxiety.