Spence 2011.

Study characteristics
Methods	Randomised controlled trial
Participants	Sample size: 42 Diagnosis: DSM‐IV PTSD Method of recruitment: recruitment from a website that offers participation in trials, adverts in local media. Method of diagnosis: MINI administered via telephone Trauma type: various Age (mean): I‐CBT: 43.0 (SD 15.2) years; wait list: 42.0 (SD 10.4) years Sex: 81% women; 19% men Location: Australia Comorbidities: unclear Adjunctive therapy: excluded Adjunctive medication: stable for 1 month Unemployment: 40% University education: unclear Exclusion criteria: currently experiencing a psychotic mental illness; severe symptoms of depression; currently highly dissociative; current CBT. Baseline PTSD: all participants met diagnostic criteria for PTSD. Baseline PCL‐C scores (mean): I‐CBT: 60.78 (SD 10.03); wait list: 57.00 (SD 9.69)
Interventions	Internet programme based on trauma‐focused CBT versus wait list Experimental arm Duration: 8 weeks Treatment protocol Lesson 1: education about the prevalence, symptoms, and treatment of PTSD, including an explanation of the functional relationship between symptoms. Lesson 2: instructions about controlling physical symptoms including dearousal strategies. Lesson 3: basic principles of cognitive therapy, including strategies for monitoring and challenging thoughts. Lesson 4: education and guidelines about practicing graded exposure. Lesson 5: education and guidelines about practicing imaginal exposure, using repeated written exposure, audio‐recording, or both, and repeatedly listening to the recording. Lesson 6: education and guidelines about challenging dysfunctional beliefs, including trauma related beliefs. Lesson 7: information about relapse prevention and constructing relapse prevention plans. Therapist contact (mean): 103.91 (SD 96.53) minutes Type of contact: telephone, e‐mail, forum Automated contact: reminders and notifications Type of therapist: clinical psychologist Treatment fidelity: not reported Comparator arm Duration: 8 weeks Treatment protocol: wait list
Outcomes	Time points for assessment: pretreatment, post‐treatment, and 3‐month follow‐up Primary outcome: PCL‐C Secondary outcome: PHQ‐9, GAD‐7, SDS
Notes	Funding source: supported by a research fellowship from the New South Wales Institute of Psychiatry. Declarations of interest among the primary researchers: contract grant sponsor: New South Wales Institute of Psychiatry
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: "Forty‐four applicants met all inclusion criteria and were randomized via a true randomization process (www.random.org), generated by an independent person."
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	High risk	Quote: "Treatment group participants had a similar diagnostic assessment at three‐month follow‐up. These assessments were conducted by JS and KS, who were not blind to the participants’ condition."
Incomplete outcome data (attrition bias) All outcomes	High risk	ITT analyses using LOCF.
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	Unclear risk	Small sample size Recruitment ceased after 4 weeks due to staff availability. Did not meet the recruitment target (indicated by power calculation) of 26 per group. Evaluated by the originators of the intervention. Time‐since‐trauma not recorded, so unsure about the requirement for the trauma to have been at least 1 month previously.

AUDIT: Alcohol Use Disorders Identification Test; BAI: Beck Anxiety Inventory; BDI‐II: Beck Depression Inventory II; B‐IPF: Brief‐Inventory of Psychosocial Functioning; CAPS: Clinician Administered PTSD Scale; CBT: cognitive behavioural therapy; CES‐D: Center for Epidemiologic Studies Depression Scale; CGI‐I: Clinical Global Impressions – Improvement; DSM‐IV: Diagnostic and Statistical Manual of Mental Disorders; FDAS: Food & Drug Analytical Services; GAD‐7: Generalized Anxiety Disorder 7; HSCL‐25: ; I‐CBT: Internet‐based cognitive behavioural therapy; IES‐R: Impact of Event Scale – Revised; ITT: intention to treat; LOCF: last observation carried forward; MINI: Mini‐International Neuropsychiatric Interview; PCL: PTSD Checklist; PCL‐C: PTSD Checklist – Civilian Version; PCL‐M: PTSD Checklist – Military Version; PDS: Posttraumatic Diagnostic Scale; PHQ‐9: Patient Health Questionnaire‐9; PSS‐I: PTSD Symptom Scale – Interview; PTSD: post‐traumatic stress disorder; QOLI: Quality of Life Inventory; SD: standard deviation; SDS: Shehan Disability Scale; SSQ: Social Support Questionnaire; TAU: treatment as usual; WIRED: Warriors Internet Recovery & EDucation.