The Benefit of Interventions to Reduce Posttraumatic Stress in Youth Exposed to Mass Trauma: A Review and Meta-Analysis

Abstract

Numerous interventions to address posttraumatic stress (PTS) in youth exposed to mass trauma have been delivered and evaluated. It remains unclear, however, which interventions work for whom and under what conditions. This report describes a meta-analysis of the effect of youth mass-trauma interventions on PTS to determine if interventions were superior to inactive controls and describes a moderator analysis to examine whether the type of event, population characteristics, or income level of the country where the intervention was delivered may have affected the observed effect sizes. A comprehensive literature search identified randomized controlled trials (RCTs) of youth mass-trauma interventions relative to inactive controls. The search identified 2,232 references, of which 25 RCTs examining 27 trials (N = 4,662 participants) were included in this meta-analysis. Intervention effects were computed as Hedge’s g estimates and combined using a random effects model. Moderator analyses were conducted to explain the observed heterogeneity among effect sizes using the following independent variables: disaster type (political violence versus natural disaster); sample type (targeted versus non-targeted); and income level of the country where the intervention was delivered (high- versus middle- versus low-income). The correlation between the estimates of the intervention effects on PTS and on functional impairment was estimated. The overall treatment effect size was converted into a number needed to treat (NNT) for a practical interpretation. The overall intervention effect was statistically significant (g = 0.57; P < .0001), indicating that interventions had a medium beneficial effect on PTS. None of the hypothesized moderators explained the heterogeneity among the intervention effects. Estimates of the intervention effects on PTS and on functional impairment were positively correlated (Spearman’s r = 0.90; P < .0001), indicating a concomitant improvement in both outcomes. These findings confirm that interventions can alleviate PTS and enhance functioning in children exposed to mass trauma. This study extends prior research by demonstrating improvement in PTS with interventions delivered to targeted and non-targeted populations, regardless of the country income level. Intervention populations and available resources should be considered when interpreting the results of intervention studies to inform recommendations for practice.

A Critical Review of Effective Child Mass Trauma Interventions: What We Know and Do Not Know from the Evidence

“…The current review synthesizes the results of 12 meta-analyses of randomized controlled trials using inactive controls to examine posttraumatic stress [14,[17][18][19], depression [14,15,18], anxiety [15,18], and functional impairment [14,16,18] outcomes in children receiving interventions for mass trauma. Two publications addressed more than one outcome [14,18].…”

“…Morina and colleagues [14] examined posttraumatic stress, depression, and functional impairment, and Purgato and colleagues [18] examined posttraumatic stress, depression, anxiety, and functional impairment [18]. Three of the publications [15][16][17] were authored by the authors of the current review. Because of the high heterogeneity in intervention effects, subgroup analyses were conducted in some of the meta-analytic studies to examine these intervention effects within subgroups that reflect the characteristics of the individual trials.…”

“…Moderator analysis was used to identify factors that explained the variation in results reported by studies with the objective of determining why the effect of the intervention differed across studies. Intervention moderators are reviewed to the extent that they were explored in these meta-analyses [15][16][17][18]. Moderators were categorical variables including event type (e.g., natural vs. manmade), child characteristics (e.g., demographics, exposure), contextual factors (e.g., geographic location, country income level), characteristics of interventions (e.g., individual vs. group), and aspects of intervention delivery (e.g., dose).…”

“…Over the last 20 years, numerous interventions have been developed and evaluated for use with children exposed to mass trauma generating systematic qualitative [9,10] and methodological [11][12][13] reviews. More recently, eight publications have reported metaanalyses of randomized controlled trials of child mass trauma interventions including six with studies using only inactive controls [14][15][16][17][18][19] and two with studies using both active and inactive controls [20,21]. These meta-analyses have explored intervention effects on posttraumatic stress [14,[17][18][19][20][21], depression [14,15,18], anxiety [15,18], and functional impairment [14,16,18].…”

“…Tol and colleagues [19] also examined intervention effects on internalizing symptoms (depression or anxiety). Moderators of intervention effect were explored in some investigations [15][16][17][18]20,21]. The child disaster mental health intervention literature, including meta-analytic studies, is now extensive and warrants a critical review.…”