Mills 2012.
| Methods | Design: RCT | |
| Participants |
Setting: Participants were seen on an outpatient basis and were recruited from substance use treatment services, media advertisements, and practitioner referrals. Inclusion criteria: Past‐month DSM‐IV‐TR diagnoses of PTSD and substance dependence, age 18 years or older, and fluency in English. Exclusion criteria: Individuals were excluded from participating if they were currently suicidal (expressed suicidal ideation accompanied by a plan and intent), had a recent history of self harm (past 6 months), had current active symptoms of psychosis, or experienced cognitive impairment severe enough to impede treatment. PTSD diagnosis: All participants met full diagnosis for PTSD as measured by the CAPS. Sample size: 334 individuals were assessed for eligibility; 103 were randomised, and all were included in the analyses. SUD type and diagnosis: All participants were reported to be substance dependent. Participants were polydrug users and had used a mean of 4 drug classes in the previous month. Mean age: 33.7 (SD = 7.9) years Gender: 64 (62.1%) female Ethnicity: Australian born: 87 (84.5%); 6 (5.8%) Aboriginal or Torres Strait Islander Country: Australia |
|
| Interventions |
Group 1: Concurrent Treatment of PTSD and Substance Use Disorders Using Prolonged Exposure (COPE): n = 55. COPE is a modified version of Concurrent Treatment of PTSD and Cocaine Dependence. The model represents an integration of existing evidence‐based manualised CBT interventions for PTSD and substance dependence. Intervention consists of 13 individual‐based 90‐minute sessions (i.e. 19.5 hours) delivered by a clinical psychologist. Although designed to be delivered weekly, flexibility was permitted. Treatment components include motivational enhancement and CBT for substance use; psycho‐education relating to both disorders and their interaction; in vivo exposure; imaginal exposure; and cognitive therapy for PTSD. The final session was dedicated to providing a review of the treatment, devising an aftercare plan, and termination of therapy. Group 2: Usual treatment: n = 48. Both the treatment and the control group were able to engage in usual treatment for substance dependence. As such, participants could access any type of substance use treatment currently available in the community, including outpatient counselling, inpatient or outpatient detoxification, residential rehabilitation, and pharmacotherapies (e.g. methadone, buprenorphine, buprenorphine plus naloxone, naltrexone). Experimental intervention modality: Combined |
|
| Outcomes |
PTSD: CAPS SUD: CIDI Treatment acceptability: Data are reported for number of participants attending at least 1 treatment session; number attending at least 1 imaginal exposure session; and number attending all sessions. Other: BDI, STAI, IPDE Follow‐up: 6 weeks, 3 and 9 months postbaseline |
|
| Notes | The study concluded with a lower sample size than planned due to a low recruitment rate. It is unclear why there is such sizeable difference between the numbers of participants randomised to the 2 conditions | |
| Risk of bias | ||
| Bias | Authors' judgement | Support for judgement |
| Random sequence generation (selection bias) | Low risk | "Block randomization was conducted in groups of 10, stratified according to sex ... " |
| Allocation concealment (selection bias) | Low risk | " ... by a person independent of the research." |
| Blinding of participants and personnel (performance bias) All outcomes | High risk | Participants and personnel were not blinded to allocation |
| Blinding of outcome assessment (detection bias) All outcomes | Low risk | Interviews were administered by 2 trained research officers blinded to group allocation |
| Incomplete outcome data (attrition bias) All outcomes | Low risk | Outcome data were analysed on an ITT basis. Missing data were imputed using multiple imputation |
| Selective reporting (reporting bias) | Low risk | Key outcomes are as specified in the protocol registered with the World Health Organization's trials portal |
| Other bias | High risk | Participants in the control group were more likely to have reported a history of childhood sexual abuse. This was controlled for in analyses. There was considerable variability in the time taken to complete treatment, with some participants continuing treatment well beyond the planned treatment period of 13 weeks and at least 1 receiving treatment around the final follow‐up point |