| Methods |
RCT, 3 parallel groups in equal numbers: paced respiration, muscle relaxation and α‐wave biofeedback (control) |
| Participants |
This study randomly assigned 33 participants to muscle relaxation, paced respiration or placebo control (n = 11 per group). 11 participants in paced respiration, in muscle relaxation and in α‐wave feedback group. All postmenopausal women experienced at least 5 hot flushes per day and had been amenorrhoeic ≥ 1 year |
| Interventions |
Participants in paced respiration group were instructed to breathe 6 to 8 cycles/min and to increase the amplitude of the abdominal tracing. Participants in the muscle relaxation group were initially trained to systematically tense and then relax 16 gross muscle groups. Participants in the α‐wave feedback group received visual feedback for the production of 8 to 13 Hz electroencephalographic activity. Training was done in three 10‐minute trials, separated by 5‐minute rest periods |
| Outcomes |
Hot flush frequency during 24‐hour ambulatory monitoring, respiration rate and tidal volume |
| Notes |
Trial received funding from the National Institute on Aging |
| Risk of bias |
| Bias |
Authors' judgement |
Support for judgement |
| Random sequence generation (selection bias) |
Unclear risk |
Method of randomisation not reported |
| Allocation concealment (selection bias) |
Unclear risk |
No information on allocation concealment |
| Blinding of participants and personnel (performance bias)
All outcomes |
Unclear risk |
No information on blinding |
| Blinding of outcome assessment (detection bias)
All outcomes |
Unclear risk |
Insufficient information to permit a judgement of yes or no |
| Incomplete outcome data (attrition bias)
All outcomes |
Low risk |
11 participants randomly assigned to paced respiration, 11 to muscle relaxation and 11 to α‐wave feedback group. All participants were included in the final analysis |
| Selective reporting (reporting bias) |
Low risk |
Number of flushes was measured over a 24‐hour period, and other outcomes were objectively measured by using appropriate equipment, thus less prone to bias. All outcomes were reported |
| Other bias |
Unclear risk |
Duration of the 3 interventions was not specified. Unclear information regarding the exact time when outcome assessment was performed |
