Previous meta-analyses of psychotherapies for children and adolescents with post-traumatic stress disorder (PTSD) did not investigate whether treatment efficacy is diminished when patients report multiple (versus single) traumas.

To examine whether efficacy of psychological interventions for paediatric PTSD is diminished when patients report multiple (versus single) traumas.

We systematically searched PsycInfo, MEDLINE, Web of Science and PTSDpubs on 21 April 2022 and included randomised controlled trials (RCTs) meeting the following criteria: (a) random allocation; (b) all participants presented with partial or full PTSD; (c) PTSD is the primary treatment focus; (d) sample mean age <19 years; (e) sample size n ≥ 20. Trauma frequency was analysed as a dichotomous (single versus ≥2 traumas) and continuous (mean number of exposures) potential moderator of efficacy.

Of the 57 eligible RCTs (n = 4295), 51 RCTs were included in quantitative analyses. Relative to passive control conditions, interventions were found effective for single-trauma-related PTSD (Hedges’ g = 1.09; 95% CI 0.70–1.48; k = 8 trials) and multiple-trauma-related PTSD (g = 1.11; 95% CI 0.74–1.47; k = 12). Psychotherapies were also more effective than active control conditions in reducing multiple-trauma-related PTSD. Comparison with active control conditions regarding single-event PTSD was not possible owing to scarcity (k = 1) of available trials. Efficacy did not differ with trauma exposure frequency irrespective of its operationalisation and subgroup analyses (e.g. trauma-focused cognitive–behavioural therapy only).

The current evidence base suggests that psychological interventions for paediatric PTSD can effectively treat PTSD in populations reporting single and multiple traumas. Future trials for PTSD following single-event trauma need to involve active control conditions.

Trauma and traumatic bereavement have well-known consequences for mental health, but little is known about long-term adjustment, particularly with respect to health-protective factors.

To assess the levels of anxiety/depression and perceived social support among the survivors and the bereaved 26 years after the Scandinavian Star ferry disaster compared with expected levels from the general population.

Anxiety/depression and social support were assessed in face-to-face interviews with the survivors and the bereaved (N = 165, response rate 58%). Expected scores were calculated for each participant based on the means and proportions for each age and gender combination from a general population sample. We computed the ratio between expected and observed scores, standardised mean differences with 95% confidence intervals and standardised effect sizes.

We found an elevated level of anxiety/depression symptoms in the victims (Mdiff = 0.28, 95% CI 0.18, 0.38; effect size 0.43, 95% CI 0.31, 0.55) and a significant excess of individuals with a clinically significant level of symptoms. The observed level of perceived social support was significantly lower than that expected (Mdiff = −0.57, 95% CI −0.70, −0.44; effect size −0.73, 95% CI −0.89, −0.57). This was the case for both survivors and those who were bereaved and for both men and women.

This study reveals that disaster survivors and the bereaved reported elevated levels of anxiety and depression symptoms 26 years after the event. They also reported a markedly reduced level of social support. Traumas and post-traumatic responses may thus cause lasting harm to interpersonal relationships.

None.