Mustian 2013.
| Methods | Randomised controlled trial | |
| Participants | Women with diagnosed non‐metastatic breast cancer between 2 and 24 months after surgery, chemotherapy and/or radiation with sleep disturbances Recruited from Community Clinical Oncology Program (CCOP) clinics and through the use of flyers in communities Mean age 54.1 years N = 309 |
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| Interventions | • Yoga for Cancer Survivors (YOCAS) programme (yoga postures, breathing techniques, meditation), 4 weeks, twice weekly for 75 minutes • Wait‐list, no treatment |
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| Outcomes | Sleep disturbances (Pittsburgh Sleep Quality Index) at week 4 Safety (adverse events) at week 4 |
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| Notes | Subgroup analysis for women with diagnosed breast cancer was derived from a study on patients with mixed cancer sites; unpublished sample size, means and standard deviations for Pittsburgh Sleep Quality Index were provided by study authors upon request. | |
| Risk of bias | ||
| Bias | Authors' judgement | Support for judgement |
| Random sequence generation (selection bias) | Low risk | "Survivors were recruited in cohorts (n = 20 to 30), stratified by sex and baseline sleep disturbance (two levels…) and randomly assigned to both groups at each CCOP. Group assignment was determined by a computer‐generated random numbers table in blocks of two and an allocation ratio of 1:1." |
| Allocation concealment (selection bias) | Low risk | "Allocation was concealed from coordinators until after they registered the participants by using a computerized Web site that generated an e‐mail to the research base and CCOP site." |
| Blinding of participants and personnel (performance bias) All outcomes | High risk | "Participants received their allocation assignment after completing baseline assessments." |
| Blinding of outcome assessment (detection bias) All outcomes | Low risk | "The study primary investigator and biostatistician were blinded to allocation." |
| Incomplete outcome data (attrition bias) All outcomes | Low risk | 22% of enrolled participants were lost to follow‐up and/or did not provide fully evaluable data; intention‐to‐treat analysis |
| Selective reporting (reporting bias) | High risk | Published substudy with additional questionnaires that were not mentioned in the original study protocol |
| Other bias | Low risk | No hint of other bias |