Litz 2007.

Study characteristics
Methods	Randomised controlled trial
Participants	Sample size: 45 Diagnosis: DSM‐IV PTSD Method of recruitment: advertisements and presentations at department of defence sites Method of diagnosis: PSS‐I Trauma type: combat exposure: 9/11 attack on the Pentagon, or combat in Iraq or Afghanistan Age (mean): Internet CBT: 38.63 (SD 9.41) years; Internet supportive counselling: 39.86 (SD 7.72) years Sex: unclear Location: US Comorbidities: unclear Adjunctive therapy: excluded Adjunctive medication: unclear Unemployment: unclear University education: unclear Exclusion criteria: active substance dependence; current suicidal ideation; history of psychotic disorder; aged < 21 or > 65 years; PTSD or depression immediately before the trauma; current psychiatric treatment; marked ongoing stressors; inadequate social supports; change in medication. Baseline PTSD: all participants met diagnostic criteria for PTSD. Baseline PSS‐I scores: Internet CBT: 26.71 (SD 9.02); Internet supportive counselling: 29.16 (SD 9.93)
Interventions	Internet programme based on trauma‐focused CBT with Internet psychological therapy (non‐CBT) Experimental arm Duration: 8 weeks Treatment protocol Self‐monitoring of situations that triggered trauma‐related distress. Generation of a serial ordering (hierarchy) of these trigger contexts in terms of their degree of threat or avoidance. Stress management strategies. Graduated, self‐guided, in vivo exposure to items from the personalised hierarchy (starting with the least threatening or least avoided item in week 3). 7 online trauma writing sessions. A review of progress (charts of daily symptom reports were presented), a series of didactics on relapse prevention, and the generation of a personalised plan for future challenges. Therapist contact: initial face‐to‐face (2 hours, including baseline assessment); telephone (ad‐lib); e‐mail (ad‐lib) Type of contact: online, e‐mail, face‐to‐face Automated contact: none Type of therapist: unclear Treatment fidelity: not reported Comparator arm Duration: 8 weeks Treatment protocol Monitoring non‐trauma‐related concerns and online writing about these experiences. Psychoeducation materials were available about the psychological, emotional, and cognitive effects of trauma, but this was provided for information only, and no action was required. Supportive counselling group was asked to visit the website daily to report their symptoms, read about stress and stress management, and write about current concerns. Website allowed the participants to ask for an immediate telephone call from their therapists, and they were called periodically by their study therapist to check in on how they were doing and to answer any questions they might have about the self‐help program. Through e‐mail and the telephone, supportive counselling therapists were instructed to be empathic and validating, non‐directive and supportive, and to focus on non‐trauma‐related present‐day concerns. In week 8, participants in the supportive counselling arm were asked to plan ways of using what they learned in the course of the therapy from that point forward, and to plan for future stressors; they also were shown graphs of the course of their progress (symptom reporting). Therapist contact: initial face‐to‐face (2 hours, including baseline assessment), telephone (ad‐lib), e‐mail (ad‐lib) Type of contact: online, e‐mail, face‐to‐face Automated contact: none Type of therapist: unclear
Outcomes	Time points for assessment: pretreatment, post‐treatment, 3‐month follow‐up, and 6‐month follow‐up Primary outcome: PSS‐I Secondary outcome: BDI, BAI
Notes	Funding source: supported by grant from NIHM (MH66589) Declarations of interest among the primary researchers: none
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Not reported
Allocation concealment (selection bias)	Unclear risk	Not reported
Blinding of participants and personnel (performance bias) All outcomes	High risk	Impossible to blind participants or therapists.
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Quote: "The study therapists conducted the baseline assessments in order to initially establish rapport. Clinicians blind to study arm conducted the follow‐up evaluations."
Incomplete outcome data (attrition bias) All outcomes	High risk	Authors stated that they performed ITT analyses, but only completer analyses were reported.
Selective reporting (reporting bias)	Low risk	Study protocol not available but it was clear that the published reports included all expected outcomes, including those that were prespecified.
Other bias	High risk	Small sample size Large numbers lost to 3‐month follow‐up and 6‐month follow‐up. Evaluated by the originators of the intervention.