Blanchard 2003.

Methods	Randomised controlled trial
Participants	98 road traffic accident survivors in the USA (72 women, 26 men)
Interventions	8 ‐ 12 sessions TFCBT (n = 27) vs 8 ‐ 12 sessions supportive psychotherapy (n = 27) vs waiting list (n = 24) (all three arms included in meta‐analyses)
Outcomes	IES,STAI
Notes	Therapists were practising psychologists, with over 5 years experience. Each had a cognitive behavioural orientation, but treated participants in both active treatment arms. Adherence was assessed.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	High risk	Quote "The senior author matched participants into triads, based on the CAPS score and diagnosis,and then randomly assigned triads to a therapist and to conditions within the triad." Comment: Indicates that the method of sequence generation poses the potential for bias.
Allocation concealment (selection bias)	Unclear risk	Comment: there were no reported measures of allocation concealment.
Incomplete outcome data (attrition bias) All outcomes	Low risk	Quote "When we could not obtain dropout assessment data, we substituted the initial assessment data in the intent to treat analysis." However, no reasons were reported for drop‐outs (10 from CBT, 9 from supportive psychotherapy, and 1 from waitlist).
Selective reporting (reporting bias)	Low risk	Comment: All specified and expected outcomes appear to have been reported.
Other bias	Low risk	Comment: no other sources of bias detected.
Blinding of participants and personnel (performance bias) All outcomes	High risk	Comment: Participants were aware of their allocation.
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Quote "The assessors were kept blind to treatment condition."