Nguyen 2010.

Study characteristics
Methods	RCT. 2 arms.
Participants	Number of children: 20 control, 20 treatment Sex of children: 25 M, 15 F Age range of children: 7 ‐ 12 years Mean age of children: 8.8 ± 1.59 years (intervention); 9.4 ± 1.93 years (control) Needle procedure: LP Diagnosis: leukemia Inclusion criteria: 7 ‐ 12 year olds, with leukemia, due to undergo a LP Exclusion criteria: significant hearing or visual impairment, cognitive disorder Setting: hospital oncology ward at NHP, Hanoi, Vietnam
Interventions	1. Music distraction: Children listened to music using earphones beginning 10 minutes prior to the procedure. 2. Control: Children wore earphones without music beginning 10 minutes prior to the procedure.
Outcomes	Pain measure: Child self‐report: NRS 0 ‐ 100 (during procedure) Distress measure: Spielberger State‐Trait Anxiety Inventory (STAI‐Short Form, range 6 ‐ 24) (post‐procedure) Physiological measure: Heart rate Blood pressure (systolic and diastolic) Oxygen saturation Respiratory rate Adverse events: none mentioned
Notes	Study dates: November 2007 to July 2008. Funding: none stated Conflicts of interest: none declared
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Randomized ‐ no further details. Insufficient information to permit judgment of 'low' or 'high' risk
Allocation concealment (selection bias)	Unclear risk	Unclear if all appropriate safeguards taken with assignment envelopes (i.e. sequentially‐numbered or sealed)
Blinding of participants and personnel (performance bias) All outcomes	High risk	Participants were not blinded
Blinding of outcome assessment (detection bias) All outcomes	High risk	No blinding of self‐report outcome assessment
Incomplete outcome data (attrition bias) All outcomes	Low risk	No missing data
Selective reporting (reporting bias)	Unclear risk	Insufficient information to permit judgment of 'low' or 'high' risk
Other bias	High risk	Potential source of bias related to measurement of outcomes