Jespersen 2012.

Methods	Quasi‐randomised controlled trial Design: 2‐arm parallel group design Blindness: not blinded
Participants	Traumatised refugees with sleep problems documented by PSQI score > 5 N: 15 (19 included; 4 dropped out) Age: mean 37 years; range 26 to 57 Sex: 6 males; 9 females Setting: homes of the participants Country: Denmark
Interventions	Music group (N = 9) participants listened to researcher selected music received a music player designed to be used in bed, including an ergonomic pillow Control group (N = 6) participants received an ergonomic pillow, but no music intervention Music characteristics: MusiCure compilation 'Inducing Sleep' (Tracks 1, 2, and 5; Eje 2004). Tempo 52 bpm, stable dynamic contour and repetitive structure Instruments: piano, harp, guitar, oboe, cello, and nature sounds (waves and birdsong) Length of sessions: 60 minutes Frequency of sessions: daily at bedtime Duration of intervention period: 3 weeks
Outcomes	Sleep quality (PSQI) mean (SD) change scores from baseline to post‐intervention Trauma symptoms not included in this review Well‐being not included in this review
Notes	Trial start and end dates: the trial was conducted in 2010 Funding sources: the work was supported by Trygfonden and the Danish Ministry for Refugee, Immigration and Integration Affairs
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	High risk	Used an alternation procedure based on gender
Allocation concealment (selection bias)	High risk	Allocation could be foreseen due to the alternation procedure
Blinding of participants and personnel (performance bias) All outcomes	High risk	Due to the nature of the intervention, blinding of participants was not possible. It is likely that this affected the subjective outcome measures. The intervention was used at home with no personnel involved
Blinding of outcome assessment (detection bias) All outcomes	High risk	No blinding of outcome assessment
Incomplete outcome data (attrition bias) All outcomes	High risk	4 participants dropped out. Data from dropouts were excluded in the final analyses. No missing data
Selective reporting (reporting bias)	Low risk	All outcomes were reported and included in the analysis
Other bias	High risk	Baseline difference in sleep quality with the music group experiencing more sleep problems than the control group