Bower 2012.
| Methods | Randomised controlled trial | |
| Participants | Women with diagnosed stage 0‐II breast cancer with persistent post‐treatment fatigue who had completed local and/or adjuvant cancer therapy Recruited through tumour registry mailings, newspaper advertisements and flyers Mean age 53.9 years N = 31 |
|
| Interventions | • Iyengar yoga (postures, breathing techniques), 12 weeks, twice weekly for 90 minutes • Health education, 12 weeks, once weekly for 120 minutes |
|
| Outcomes | Health‐related quality of life (Medical Outcomes Study 36‐item short‐form health survey vitality scale) at weeks 12 to 14 and week 24 Depression (Beck Depression Inventory‐II) at weeks 12 to 14 and week 24 Fatigue (Fatigue Symptom Inventory; Multidimensional Fatigue Symptom Inventory vigour subscale) at weeks 12 to 14 and week 24 Subjective Sleep Quality (Pittsburgh Sleep Quality Index) at weeks 12 to 14 and week 24 Safety (intervention‐related adverse events) |
|
| Notes | ||
| Risk of bias | ||
| Bias | Authors' judgement | Support for judgement |
| Random sequence generation (selection bias) | Low risk | "The allocation sequence was generated independently by the study statistician (R.O.) and was concealed in opaque envelopes." |
| Allocation concealment (selection bias) | Low risk | "The allocation sequence was generated independently by the study statistician (R.O.) and was concealed in opaque envelopes." |
| Blinding of participants and personnel (performance bias) All outcomes | Low risk | "On a 7‐point Likert scale ranging from 0 (not at all effective) to 6 (very effective), the mean score was 3.86 for the yoga group and 3.2 for the health education group (P = .33)." "[...] participants unavoidably are aware of the treatment that they receive. We attempted to minimize the impact of pre‐existing beliefs and expectations on study outcomes by informing participants that we were testing 2 different treatments for cancer‐related fatigue, each of which presumably was effective. This presentation appeared to have been successful, because both groups had similar, positive expectations about the efficacy of the treatment to which they had been assigned." |
| Blinding of outcome assessment (detection bias) All outcomes | Unclear risk | "Outcomes assessors for the performance tasks were blinded to group assignment, and all were trained in standardized testing procedures." No information on blinding of patient‐reported outcomes |
| Incomplete outcome data (attrition bias) All outcomes | Low risk | 12.5% dropouts in the yoga group, none in the control group; intention‐to‐treat analysis |
| Selective reporting (reporting bias) | Low risk | No protocol available but no hint of selective reporting. Reported outcomes comparable with pilot trial |
| Other bias | Low risk | No hint of other bias |