Scheeringa 2014.

Methods	Design: Randomised, placebo controlled, double‐blind study Study duration: 12 weeks (4 weeks CBT only) Follow‐up: 3 months Country: USA
Participants	Sample size: 57 children and adolescents were randomised Recruitment: Investigators attempted to contact a total of 644 potential participants: 30% were referred by other professionals, 14% referred themselves from radio and television advertisements, and 56% were contacted from the local level I trauma centre registry Inclusion criteria ‐ diagnostic classification criteria: 5 or more PTSD symptoms plus functional impairment, specific diagnostic criteria not reported Inclusion criteria ‐ rating scales: National Institute of Mental Health Diagnostic Interview Schedule for Children‐IN (DISC‐IV) Included disorders: PTSD Co‐morbidities: Not reported Gender: DCS group 66% female; placebo group 46% female Mean age: DCS group mean age 12.4 (SD 3.3); placebo group mean age 12.6 (SD 3.4) Ethnicity: DCS group 41% Black, 41% White, 14% mixed, 3% other; placebo group 43% Black, 39% White, 14% mixed, 4% other Pharmacotherapy during the study: Naturalistic prescribing allowed. Subjects must have been stable on medication for at least 4 weeks prior to treatment
Interventions	Intervention: Individuals received 12‐weekly sessions of manualized trauma‐focused cognitive behavioural therapy plus 7 doses of 50 mg d‐cycloserine 1 hour prior to sessions 5 to 11. N = 29 Comparison: Individuals received 12‐weekly sessions of manualized trauma‐focused cognitive behavioural therapy plus 7 doses of placebo 1 hour prior to sessions 5 to 11, N = 28 Therapists: Therapy was delivered by 2 masters‐level therapists trained in CBT and supervised by the authors
Outcomes	Response; withdrawals; anxiety: CPSS; co‐morbid depression: CDI; co‐morbid anxiety: SCARED
Notes	Funding from industry: No. Financial support for this study was provided by National Institute of Mental Health grant 5RC1MH088969‐02 and a 2009 National Alliance for Research on Schizophrenia and Depression (NARSAD) Independent Investigator Award (principal investigator: M.S.S.) Medication supplied by industry: Not reported Any author work for industry: Unclear, "No competing financial interests exist." Study ID: NCT01157416
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	"For each age group, we created a list of randomised numbers using the Microsoft Excel 2007 random number generator. Block randomisation in sets of four was used. Within the first set of four numbers, two were randomly assigned to CBT and DCS and two to CBT and placebo."
Allocation concealment (selection bias)	Unclear risk	Details on allocation concealment were not provided
Blinding of participants and personnel (performance bias) All outcomes	Low risk	"All research personnel were blinded except the pharmacist, who had no contact with subjects." "The study was triple‐blind as the Board, the participants, and the investigators were blind to allocation status."
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	"All research personnel were blinded except the pharmacist, who had no contact with subjects." It is not specifically stated that outcome assessors were blinded
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	A total of 72% of DCS group completed treatment and follow‐up; 64% of placebo group completed treatment and follow‐up. Reasons were not reported
Selective reporting (reporting bias)	Low risk	All outcomes stated in the protocol were reported
Other bias	Low risk	The study appears to be free of other sources of bias