Dodd 2003.

Methods	Design: randomised controlled trial Country of origin: Australia Intervention(s): resistance training programme of the ankle plantarflexors, knee extensors, and hip extensors Unit of allocation: individual
Participants	Number of participants: 21 randomised; exercise group: n = 11; control group: n = 10 Group characteristics reported for all randomised participants. Age: 8‐18 years; exercise group: mean (SD) = 12.7 (2.8) years; control group: mean (SD) = 13.5 (3.4) years Sex (male/female): 10/11; exercise group: 4/7; control group: 6/4 Ethnicity: not stated GMFCS level: level I (n = 7), level II (n = 5), level III (n = 9); exercise group: level I (n = 2), level II (n = 2), level III (n = 7); control group: level I (n = 5), level II (n = 3), level III (n = 2) Type of motor abnormality: spastic CP Anatomical distribution of CP: diplegia Inclusion criteria: aged 8‐18 years, spastic diplegia, able to walk independently with or without a walking aid (GMFCS level I‐III), able to follow commands Exclusion criteria: fixed flexion deformity at the knee, hip greater than 25 degrees or fixed equinus of more than 10 degrees, current participation in other management strategies such as serial casting, botulinum toxin or orthopaedic surgery in the previous 12 months, participation in a strength‐training programme within the previous 3 months
Interventions	Aim of the intervention: to increase muscle strength, physical activity and walking ability Type of exercise programme: resistance training. Participants also instructed to continue their normal activities including school and sport and attend usual physiotherapy provided the programme didn't include progressive resistance training (usual physiotherapy is a 45‐min consultation once or twice a month). Exercise mode: exercises to increase strength of ankle plantarflexors, knee extensors, and hip extensors i.e. bilateral heel raises, bilateral half squats, step‐ups Comparator: participants in control group: instructed to continue their normal activities including school and sport. Also attended usual physiotherapy provided the programme didn't include progressive resistance training Setting: participant's home. Unsupervised individual session Intervention provider: physiotherapist Duration of programme: 6 weeks Exercise dose: 3 sets of 8‐10 repetitions of each exercise (20‐30 min sessions). 3 times per week. Load was adjusted by adding free weights to a backpack worn by participant to ensure participants could complete 8‐12 repetitions to fatigue. At the end of 2nd and 4th week the physiotherapist visited participants and adjusted the load to ensure they can only complete between 8‐12 repetitions of each exercise. Tailoring of intervention to individual: at the first session the training load was adjusted to ensure that each participant obtained optimal strength training Fidelity to prescribed intervention: adherence monitored with a self‐report exercise diary. Mean (SD) sessions 16.8 (2.4) out of 18. Mean (SD) sets 147.7 (23.4) out of 162 Monitoring of adverse events: no adverse events reported that led to missing training sessions. 1 participant reported pressure on the shoulders from the loaded backpack. 2 participants reported mild foot and ankle discomfort during heel raises. Exercise was modified and enabled participants to continue without incident. Not stated how adverse events were monitored.
Outcomes	Assessment time points: baseline (week 0), postintervention (week 6), 12 weeks postintervention (week 18) Primary outcome: no primary outcome measure stated Outcomes: Muscle strength of ankle plantarflexors, knee extensors, and hip extensors measured using hand‐held dynamometry (recorded in kg). Gross motor function measured using dimensions D and E of the Gross Motor Function Measure. Possible range of scores 0 to 39 for dimension D and 0 to 72 for dimension E. Scores presented as percentage of total possible score (higher score indicates better gross motor function). Separate scores were calculated for dimensions D and E and a total score was calculated by combining dimensions D and E. Self‐selected walking speed over 10 m (recorded in m/min). Timed stair test. Participants walk up and down 3 steps of standard size (17.5 cm) as quickly as possible, using rails if required (recorded in s). A physiotherapist experience in assessing movement disorders assessed all outcomes. Self‐concept was measured with the Self‐Perception Profile for Children. The scale assess children's perceptions of themselves across the domains of scholastic competence, physical appearance, and behavioural conduct, as well as a global perception of their worth or esteem as a person. A higher score indicates a more positive self‐concept. This outcome was only assessed on children and adolescents aged 8 to 16 years (n = 17; exercise group, n = 10; control group, n = 7) as it is only suitable for this age group.
Notes	Source of funding: not stated Potential conflicts of interest: not stated; none perceived
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: "[p]articipants were allocated randomly to either the strength training or control group using a concealed method. Twenty‐two identical pieces of paper were placed in an opaque container, 11 with the words 'experimental group', 11 with the words 'control group' written on them. In another opaque container, the name of each participant was written on 21 separate pieces of paper. Allocation was achieved by drawing a piece of paper from each container. This process continued until all participants were allocated to a group".
Allocation concealment (selection bias)	Unclear risk	Quote: "[p]articipants were allocated randomly to either the strength training or control group using a concealed method. Twenty‐two identical pieces of paper were placed in an opaque container, 11 with the words 'experimental group', 11 with the words 'control group' written on them. In another opaque container, the name of each participant was written on 21 separate pieces of paper. Allocation was achieved by drawing a piece of paper from each container. This process continued until all participants were allocated to a group". Comment: unclear if an independent person did the allocation. Implementation of the sequence could be open to bias
Blinding of participants and personnel (performance bias) All outcomes	High risk	Comment: given the nature of the intervention participants were not blinded to treatment allocation
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Quote: "[a] physiotherapist who was blind to group allocation and experienced in assessing movement disorders took all outcome measures"
Incomplete outcome data (attrition bias) All outcomes	Low risk	Comment: low rate of missing data. 1 participant (5%) withdrew from control group, reason given
Selective reporting (reporting bias)	Unclear risk	Comment: a protocol is not available for this study and therefore unable to determine if all expected outcomes are reported. No convincing text provided to indicate that published report includes all expected outcomes
Other bias	Low risk	Comment: no other sources of bias identified