Parr 2013.

Methods	RCT.
Participants	6 individuals attending their GP who had been prescribed BZDs for longer than 3 months in Canada. 3 participants in the intervention group; 3 participants in the control group.
Interventions	Intervention group: Immediate mailed CBT plus taper. The content of the mailed CBT package included making decisions; coping with withdrawal and after; sleeping better; straight thinking; be active; finding a supporter; eating when you don't feel like it; coping with worry; planning your day; keeping on track; life after 'benzos'; returning to benzo use. It comprised 12 weekly newsletters, together with feedback on assessments and on the progress of their dose reduction.   Control group: Delayed mailed CBT, plus taper.
Outcomes	Self‐reported consumption of BZDs at baseline, and 3 months. This study had a waiting list controlled design, whereby participants in the control group received the intervention post 3 month follow‐up. Therefore, both the 6 month and 12 month data collection was not relevant for the current review.
Notes	Funding source: Not reported. Declarations of interest: Not reported.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	"Once participants were judged to be eligible to participate and consented to the trial, they completed the baseline assessments and were randomly allocated to receive M‐ CBT immediately or after 3 months. The random allocation process was conducted by an independent research associate and occurred in blocks of six participants, using a series of random permutations of the numbers 1–6 in order to ensure approximate equalisation across groups".
Allocation concealment (selection bias)	Low risk	"Envelopes were provided to the research team in numbered order and allocated to participants when they commenced with the program".
Blinding (performance bias and detection bias) All outcomes	Unclear risk	No objective measure used.
Blinding of participants and personnel (performance bias) All outcomes	High risk	No blinding or incomplete blinding, and the outcome is likely to be influenced by lack of blinding.
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	No objective measure used.
Blinding of outcome assessor (detection bias) subjective outcomes	Low risk	"At each assessment point, they returned monitoring sheets by post, and a researcher who was blind to their condition interviewed them by telephone to confirm and clarify their consumption data".
Incomplete outcome data (attrition bias) All outcomes	Low risk	Missing outcome data balanced in numbers across intervention groups, with similar reasons for missing data across groups.
Selective reporting (reporting bias)	Low risk	The study protocol is not available but the published reports include all expected outcomes, including those that were pre‐specified in the method section.