The ‘long-term’ effects of universal school-based anxiety prevention trials:A systematic review

Objective: Previous reviews demonstrate that universal school-based anxiety prevention programs are generally effective in the short-term, but have not yet provided a clear evaluation of the longer-term effects. This review focuses exclusively on randomized controlled trials (RCTs) of universal school-based anxiety prevention programs that included a follow-up at 12-months or beyond. Method: In total, 359 references from previous reviews in the field were screened; PubMed and PsychInfo were also systematically searched. Eight studies met criteria (each based on cognitive-behavioural principles) comprising 7522 children aged nine-18 years. Risk of bias in most studies was high, thus a formal meta-analysis was not conducted. Results: Three of the eight studies reported greater reductions in anxiety symptomology in the prevention group compared to the control group at post-intervention (immediate effect), and each of these studies also reported maintenance of this effect at 12-month follow-up. Two further studies reported a ‘delayed’ effect at 12-month follow-up. All five studies that reported prevention effects were evaluating the FRIENDS program, and estimated effect sizes at 12-months follow-up varied from 0.2 to 0.69 (Hedges g). The final three studies (evaluating different programs) reported no immediate or long-term effects. Conclusions: The findings from this review suggest that the effects of some universally delivered school-based anxiety prevention trials can last up to 12-months, but this may depend on various factors (including program-type). It was not possible to draw firm conclusions regarding the influence of delivery mode (teacher versus health professional), parent sessions or child booster sessions. Further high quality RCTs with long-term follow-up periods are needed.