Beck 2009.

Methods	Randomised controlled trial
Participants	44 motor vehicle accident survivors (in the USA) with DSM‐IV PTSD (36 women, 8 men)
Interventions	Group TFCBT (n = 17) vs minimum contact (n = 16)
Outcomes	CAPS, IES‐R, BAI, BDI, ODI, PS‐MPI
Notes	Experienced therapists. Treatment adherence was assessed, as was competence.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Quote "Groups of four to seven individuals were formed as participants became eligible; a given group then was randomly assigned to either GCBT or MCC conditions." Comment: Method used to generate the allocation sequence is not described in sufficient detail to assess the probability that it would produce comparable groups.
Allocation concealment (selection bias)	Unclear risk	Quote "Groups of four to seven individuals were formed as participants became eligible; a given group then was randomly assigned to either GCBT or MCC conditions." Comment: There is no mention of any measures taken to conceal allocation
Incomplete outcome data (attrition bias) All outcomes	High risk	Comment: Completers data were analysed. 7 individuals dropped out of the treatment group and 2 from minimum contact. No reasons were given for drop‐out.
Selective reporting (reporting bias)	Low risk	All specified outcomes appear to have been reported, although results are discussed in terms of completers.
Other bias	Low risk	Comment: There were no other obvious sources of bias.
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 "Interviews for the POST and FU assessments were administered by an individual who had not conducted the pre‐treatment assessment and was unaware of patients' treatment status and their time of assessment (POST versus FU)."