Hsieh 2018.

Study characteristics
Methods	Randomised controlled two‐arm parallel trial
Participants	52 healthy children with symptomatic flexible flatfoot Age: all approximated 6 years ‐ treatment group 6.9 (0.6) years, control group 6.2 (0.4) years Gender: (28 M, 24 F) Location: Shin Kong Wu Ho‐Su Memorial Hospital, Taiwan Setting: Dept Physical Medicine and Rehabilitation Inclusion criteria: symptomatic flexible flatfoot (pain over the foot or calf, fatigue after prolonged walking, and gait disturbances) Exclusion criteria: history of foot injury or surgery, foot abnormalities affecting locomotion or foot mobility, or a confirmed diagnosis of developmental delays, such as developmental co‐ordination disorder and neurological deficits Baseline characteristics: treatment group had significantly lower scores for PODCI (transfer and mobility), PedsQL (physical, psychological, total health)
Interventions	Treatment group (N = 26): thermoplastic insoles, heat moulded to child's feet (CPFOs) Control group (N = 26): no treatment
Outcomes	Physical activity: timed 10‐m walk, stair ascent, timed up and go, chair rise Physical function: parent reported PODCI (Chinese version) Psychometric: PODCI, PedsQL (parent report)
Source of funding	Multiple research grants from Shin Kong Wu Ho‐Su Memoril Hospital, and Ministry of Science and Technology, Taiwan
Notes	Trial ran for 12 weeks Flatfoot assessment: ND test, FPI‐6, lat and AP x‐rays, Beighton score Self‐selected usual footwear Insole use suggested to be 5 hours/day
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	The participants were randomly assigned to the treatment group (with customized insoles) or the control group (without customized insoles) according to computer‐generated random numbers (Fig. 1).
Allocation concealment (selection bias)	Low risk	Allocation was initially concealed. A sealed envelope was opened for each consecutive participant to reveal the participant’s group allocation when the participant was recruited to the study. One physician enrolled all participants, and another investigator generated the allocation sequence and assigned the participants to their groups.
Blinding of participants and personnel (performance bias) All outcomes	High risk	Control group had no orthotic intervention
Blinding of outcome assessment (detection bias) ‐ self‐reported outcomes (e.g., pain, function)	High risk	Due to nature of intervention
Blinding of outcome assessment (detection bias) ‐ objective outcomes	High risk	High risk for primary outcome of pain as participants were not blinded. Secondary outcomes that were assessed by a blinded assessor had low risk of bias.
Incomplete outcome data (attrition bias) All outcomes	Low risk	Numbers and reasons provided for missing outcome data. Number was small and reason provided unlikely to be due to the intervention.
Selective reporting (reporting bias)	High risk	ClinicalTrials.gov (NCT02414087) The published study included more outcomes than are listed in the trial registry.
Other bias	Low risk	none apparent