Barron 2016.

Study characteristics
Methods	Study design: RCT  Unit of allocation: individual  Duration of study: started at beginning of 2015. End not clear
Participants	Country: Palestine  Income classification: lower‐middle income  Geographical scope: rural. 10 villages (Jabaa, Hezma, Anata, Bo Dees, Bethany, Bir Nabala, Qatana, Shuafat, Alram, Biet Anan) near East Jerusalem along the separation wall  Healthcare setting: school  Mental health condition: PTS  Population (mention whether patient, carer, dyad): adolescents  1. Age: 11 to 15 years  2. Gender: both  3. Socioeconomic background: lived in area with high military presence  4. Inclusion criteria (including threshold cutoff score of measurement tool) a. Participants were randomly selected from 10 randomly selected high schools (70 in the geographical area) situated in 10 villages b. Students fulfilling criteria indicative of PTSD on the CRIES–8, that is, score ≥ 17 on intrusion and avoidance subscales  5. Exclusion criteria  a. Not specified
Interventions	Stated purpose: to assess effects of a cognitive‐behavioural group intervention, Teaching Recovery Techniques (TRT), for adolescents with high levels of post‐traumatic stress (n = 154) from villages in occupied Palestine  INTERVENTION: Teaching Recovery Technique (n = 75)  Delivered by: community professional (CP) Title/name of PW and number: school counsellors ‐ 1  1. Selection: not specified  2. Educational background: not specified  3. Training (contents, duration, by whom): school counsellors received 3 days of training in programme delivery by 2 expert trainers from the Children and War Foundation covering programme values, content, and processes. Training methods included information giving, modelling, experiential learning, reflection, and feedback  4. Supervision: counsellors met monthly in pairs and in small groups for supervision to prepare and reflect on lesson delivery  Intervention details: TRT programme was developed by the Children and War Foundation, Bergen  1. Duration/frequency: 5 sessions, duration not stated  2. Content of intervention (by type of health worker and per patient/carer): Teaching Recovery Technique. This cognitive‐behavioural programme includes 5 sessions that focus on normalising trauma and strategies for intrusive memories, hyperarousal, and avoidance symptoms of PTS. The group‐delivered programme, based on CBT, focuses specifically on children’s symptoms of PTSD. The 5 sessions help students to understand the causes of trauma and to recognise signs and symptoms. Adolescents are taught a range of coping skills to stop flashbacks and other intrusive images, sounds, or smells. Student hyperarousal is addressed through stabilisation and relaxation techniques and phobic avoidance behaviour is gradually desensitised through use of relaxation with anxiety and anger hierarchies  CONTROL (n = 64) No care. Wait‐list includes students who were not in the intervention. Participants in wait‐list received their usual social education curriculum involving art, civic education, geography, history, and national education; intervention group experienced TRT   CO‐INTERVENTIONS: none
Outcomes	Patients  1. Exposure to War Stressors Questionnaire (EWSQ)  2. CRIES–13*  3. Depression Self‐Rating Scale (DSRS)*  4. Adolescent Dissociative Experiences Scale (ADES)*  Carers  None  Process/health workers  Programme fidelity measured through presenter self‐report and observer report of programme delivery (page 968)   Economic outcomes (and where these can be found, e.g. reference or table number)  Assessment of future TRT delivery and evaluation; analysis of costs was calculated for 10 counsellors and 2 local rather than international trainers delivering TRT within their own geographical location (can be found within the paper page 968)  (asterisk for study's primary outcomes; star: outcomes that we have not reported in this review)  Time points: baseline, 2 weeks post intervention
Notes	Source of funding: Children and War Foundation  Notes on validation of instruments (screening and outcomes): none  Additional information(e.g. provided by authors, existence of a published study protocol): declaration of interests ‐ none Handling the data (e.g. imputed values/other calculations we have made): omnibus multi‐variate analyses were conducted on all standardised measures and subscales. Following analysis of intervention and wait‐list data from participants who completed the TRT and from pretest and post‐test measures (n = 139), an intention‐to‐treat analysis (ITT) was conducted on all participants in both conditions, when at least pretest data were available. A conservative estimate of treatment was used when participant pretest scores were also used as post‐test scores. An ITT effect size analysis was then conducted on PTSD, depression, and dissociation between intervention and wait‐list participants  Prospective trial registration number: not provided
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: "school counselors randomly allocated adolescents to TRT and wait list groups by tossing a coin for each participant" Judgement comment: tossing a coin is considered random allocation
Allocation concealment (selection bias)	Unclear risk	Judgement comment: allocation was randomised, but if school counsellors performed randomisation, this is not concealed. Unclear whether efforts were made to conceal allocation
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Participants and personnel were not blinded, but this was unlikely to affect the outcome
Blinding of outcome assessment (detection bias) all outcomes	High risk	No information regarding blinding of outcome assessors was given
Baseline outcome measurements similar	Low risk	Similar scores for PTSD symptoms, depression, and dissociation at baseline
Baseline characteristics similar?	Unclear risk	No table. Data not clearly reported. Intervention group was more likely to be in public female schools and more likely to be female. Depression and exposure to stressors seemed to be higher among women
Incomplete outcome data (attrition bias) Efficacy data	Unclear risk	Intention‐to‐treat analysis. More dropout in waiting‐list compared to intervention group due to military violence (~ 10% across groups). Not clear whether this would have biased results
Protection against contamination	Low risk	Judgement comment: students within schools were allocated to 1 of 2 interventions. Students receiving the intervention may have influenced students on the wait‐list, although this is unlikely to have a big impact on results
Selective reporting (reporting bias)	Unclear risk	No reference to protocol or to online trial registration. All items in the methods are also reported in the results
Other bias	Low risk	No other sources of bias were found