Momennasab 2018.

Study characteristics
Methods	Study type: multicentre, RCT Design: 3‐arm, parallel group design Blinding: single blind
Participants	Sample: adults with chronic renal failure  n: 105 randomised (68 included in this review). 102 completed and included in the analyses Age: mean 49.86 (SD 11.12; range 18–60) years Sex: 56 men, 46 women (reported only for the 102 participants completing the trial) Setting: participants' homes Country: Iran
Interventions	Intervention 1 (n = 33): bedtime music group. Standard treatment and listening to music at bedtime. Researcher‐chosen music. Participants administered the music themselves. They received a CD with the intervention music. The listening device was not reported. Music characteristics: 6‐piece piano improvisation created by Taylor Mesple (2015) in New Age (relaxation) genre Length of sessions: 50 minutes Frequency of sessions: daily at bedtime Duration of intervention period: 4 weeks Intervention 2 (n = 34): daytime music group (not included in review). Standard treatment and listening to music during haemodialysis Control (n = 35): standard treatment
Outcomes	Sleep quality (assessed with PSQI) mean (SD) at baseline and postintervention scores for components (sleep latency, sleep duration, sleep efficiency, sleep disturbance, sleep medication, daytime dysfunction, subjective sleep quality)
Notes	Trial start and end dates: May to December 2016 Funding sources: financially supported by the Vice‐Chancellor for Research Affairs, Shiraz University of Medical Sciences, Iran (Grant No 10571). Protocol registration: Iranian Registry of Clinical Trials (IRCT2016050217546N5)
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Comment: participants were allocated into 2 interventions and 1 control group by block randomisation with a block size of 3.
Allocation concealment (selection bias)	High risk	Comment: with 3 groups and a fixed block size of 3, you would be able to foresee every third participant.
Blinding of participants and personnel (performance bias) All outcomes	High risk	Comment: it was not possible to blind participants to the music intervention.
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Quote: "Data collection and analysis were carried out by a research assistant and a statistician who were blinded to the patient allocation groups" (Momennasab 2018, p 88).
Incomplete outcome data (attrition bias) All outcomes	Low risk	Comment: low attrition rate that is reported satisfactorily.
Selective reporting (reporting bias)	Low risk	Comment: protocol available and outcomes well reported.
Other bias	Low risk	Comment: no indication of additional bias.