Liu 2016.

Study characteristics
Methods	Study type: RCT Design: 2‐arm, parallel group design Blinding: not blinded
Participants	Sample: pregnant women of 18–34 weeks of gestation, with sleep problems documented by PSQI scores > 5 n: 128 randomised, 121 completed and included in the analyses Age: not reported Sex: women Setting: participants' homes Country: Taiwan
Interventions	Intervention (n = 65): music group. Standard prenatal care and music listening. Participants could choose among 5 types of researcher‐selected sedative music. They administered the music themselves. The listening device was not reported. Music characteristics: the choices of music included 5 CDs of different genres (Taiwanese orchestral music, western classical music, nature sounds, lullabies and crystal music). The music had a slow tempo (60–80 bpm) and the relaxing properties were confirmed by pregnant women in a pilot investigation. Length of sessions: minimum 30 minutes Frequency of sessions: daily at bedtime Duration of intervention period: 14 days Control (n = 63): standard prenatal care
Outcomes	Sleep quality (assessed with PSQI) mean (SD) at baseline and post‐intervention Anxiety (assessed with STAI) mean (SD) at baseline and post‐intervention Perceived stress (assessed with PSS)a mean (SD) at baseline and post‐intervention aOutcome not included in this review
Notes	Trial start and end dates: no information provided Funding sources: funded by the National Science Council of Taiwan Protocol registration: none found
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Comment: randomisation procedure not clearly described.
Allocation concealment (selection bias)	Unclear risk	Comment: unclear information on the randomisation procedure and no information on measures taken to conceal allocation.
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	High risk	Comment: no blinding of outcome assessors.
Incomplete outcome data (attrition bias) All outcomes	Low risk	Comment: attrition was low, balanced and well reported.
Selective reporting (reporting bias)	Low risk	Comment: no study protocol was found. There was no indication of reporting bias.
Other bias	Low risk	Comment: no indication of additional bias.