Barwood 2000.

Methods	Method of randomisation: randomisation performed using envelopes prepared in blocks of 8, with equal numbers of each instruction in each group (restricted randomisation) Blinding: the clinician who injected BoNT‐A was not blinded. There was blinding of children, parents, carers, and other investigators. Intention‐to‐treat analysis: no Loss of follow‐up: no losses to follow‐up Unit of analysis: child
Participants	Place: 1 centre in Australia Period of study: not described Number assigned: 16 Number assessed: 16 8 BoNT‐A group 8 placebo group Inclusion criteria: Spastic CP (severe diplegia or quadriplegia) Aged 2 to 10 years Clinical and radiological evidence of hips at risk (< 40° combined range with MP in excess of 40% on at least 1 side, or an increase in MP of more than 10% in 1 year) Scheduled for isolated hip adductors release Exclusion criteria: Children outside the age range Lack of informed consent Previous hip surgery Medication for spasticity Injections of BoNT‐A in the previous year Age: BoNT‐A group (mean (2 SE)): 4.3 (1.3) Placebo group (mean (2 SE)): 5.0 (1.6) Gender: BoNT‐A group: 3 males; 5 females Placebo group: 3 males; 5 females Motor distribution: BoNT‐A group: 2 diplegia; 6 quadriplegia Placebo group: 1 diplegia; 7 quadriplegia GMFCS: BoNT‐A group: 2 level IV; 6 level V Placebo group: 2 level IV; 6 level V
Interventions	BoNT‐A group: Single BoNT‐A injection (onabotulinumtoxinA) 5 to 10 days before hip adductors surgery into the hip adductors (8 U/kg/child) Surgical lengthening of adductor longus and gracilis, lengthening of adductor brevis partially or completely until 30° to 40° of hip abduction in flexion for each side. Psoas tenotomy at the lesser trochanter for children with a hip flexion contracture exceeding 20°. Abduction plasters with the hip extended and abducted for 4 weeks. Fixed abduction brace for a further 3 to 6 months Placebo group: Saline injections and hip adductors surgery in the same conditions as above
Outcomes	Length of follow‐up: Follow‐up of 3 months to document readmission rates During inpatient stay there were hourly assessments of pain scores by the nursing staff and 8 hourly by the 2 observers Primary outcomes: Pain scores Secondary outcomes: Assessment of nausea, vomiting and sedation Analgesic requirements Complications Length of admission Readmission rate
Notes	Comments: none Source of funding: 1 of the study authors, S Barwood, is funded by the Brockhoff Foundation, and another, R Boyd, is funded in part by a National Health and Medical Research Council Grant (no. 980753) Conflicts of interest: not reported
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Comment: predetermined list (block randomisation)
Allocation concealment (selection bias)	Low risk	Comment: allocation done using opaque, sealed envelopes
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Comment: participants blinded to intervention. The clinician who injected the BoNT‐A was not blinded.
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Comment: other investigators were unaware of group allocation
Incomplete outcome data (attrition bias) All outcomes	Low risk	Comment: no incomplete outcome data
Selective reporting (reporting bias)	Unclear risk	Comment: study protocol not available. Most of the relevant outcomes were reported.
Other bias	Low risk	Comment: no other sources of bias