de Bruin 2010a.

Methods	Parallel group design. Method of randomisation not stated. Method of analysis not described. Treated as outpatients 3 times per week for a 13‐week period. Assessed at baseline and immediately after treatment. Assessors were blinded.
Participants	16 participants in the cueing group and 17 participants in the control group. Dropouts 4 (cueing), 3 (control). Participants' mean age 64.1 years (cueing), 67.0 years (control); male/female 6/5 (cueing), 5/6 (control); Hoehn and Yahr 2.3 (cueing), 2.1 (control); mean duration of PD 6.4 years (cueing), 4.5 years (control). No baseline characteristics were given for the dropout. Inclusion criteria: diagnosis of Parkinson's disease (United Kingdom Brain Bank Criteria), Hoehn and Yahr stage 2 to 3, stable medication regimen, independently mobile without the use of a walking aid, and intact hearing. Exclusion criteria: diagnosis of less than 1 year, undergone deep brain stimulation surgery, experience regular freezing episodes, unable to ambulate independently in the community, presence of neurological disorders or comorbidities likely to affect gait, scoring 24 or less on the MMSE and/or already listening to music.
Interventions	Cueing: Walking at a self‐selected pace for 30 minutes, 3 times per week whilst listening to a preloaded music battery on an MP3 player. The music battery was individualised for each participant matching music preferences and the cadence of their preferred walking speed. Control: Continued with their regular activities. Drug therapy was not described.
Outcomes	Speed. Stride time. Stride length. Cadence. Stride time variability. UPDRS (III) score. Examined on medications at the same time of day.
Notes	Compliance in the intervention group was good. 2 subjects in the music group took a 1 week break.
Risk of bias
Bias	Authors' judgement	Support for judgement
Eligibility Criteria	Low risk
Randomisation Method	Unclear risk	Randomisation method was not stated.
Concealment of Allocation	Unclear risk	Randomisation method was not stated.
Similarity at Baseline	Low risk
Withdrawals Described	High risk	21% withdrawals.
Intention To Treat Analysis	Unclear risk	Method of analysis not described.
Cointerventions Constant	Unclear risk	Drug therapy was not described.
Blinded Assessors	Low risk	UPDRS evaluator was blinded to subject group assignment.