Inoue 2006.

Methods	Mulitcenter (12 centres in Gunma and Saitama, Japan) prospective non‐blinded randomised. September 2000 to March 2005.
Participants	588 children referred to the medical institutions. 410 found to be ineligible (389 because parents decided against participation, 17 because of a previous diagnosis of KD, and 4 because a coronary artery abnormality was present before randomisation) 178 participants who were all diagnosed with KD (had at least 5 of the following: fever (> 38 °C), non‐exudative conjunctival injection, changes in the oropharynx (including mucosal erythema; dry, cracked lips; and "strawberry tongue"), changes in the extremities (including palmar and plantar erythema), oedema of the hands and feet or periungual desquamination, rash and cervical lymphadenopathy Groups well balanced in respect of baseline demographic and clinical characteristics, alongside risk score. All participants followed up for at least 2 months (range 2 to 50 months). Control: 88 Steroid: 90
Interventions	Control: IVIG 1 g/kg/day for 2 days given over 12 h Aspirin 30 mg/kg/day decreased to 5 mg/kg/day once CRP resolved Treatment: IVIG 1 g/kg/day for 2 days given over 12 h Aspirin 30 mg/kg/day decreased to 5 mg/kg/day once CRP resolved Prednisolone sodium succinate 2 mg/kg/day in 3 divided doses, intravenous until fever resolved, then given orally until CRP normalised. Once CRP normalised prednisolone was given orally in tapering doses over 15 days in 5‐day steps (2 mg/kg/day for 5 days, 1 mg/kg/day for 5 days, then 0.5 mg/kg/day for 5 days). If there was difficulty with oral delivery, doses were given IV Excluding 1 participant whose steroid treatment was discontinued at the discretion of the treating physician, duration of steroid treatment 18 to 100 days (median 23 days). Total dose of prednisolone ranged from 23.5 to 90 mg/kg (median 32 mg/kg)
Outcomes	Primary: Detection of coronary artery abnormality (luminal diameter > 3.0 mm in a child < 5 yrs, or > 4.0 mm in a child > 5 yrs, when the internal diameter of a segment was at least 1.5 times that of an adjacent segment, or when a luminal contour was clearly irregular) Secondary: Duration of fever after initial treatment Time to normalisation of CRP level (< 5 mg/dL) Incidence of treatment failure and recurrence
Notes	Study terminated on 31 March 2005 by data monitoring committee at the time of the deadline despite a lower enrolment rate than expected Unclear source of funding
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Quote: "centre randomly assigned the patient" Comment: no clear statement of mechanism for random assignment
Allocation concealment (selection bias)	Low risk	Quote: "Centrally maintained table of random numbers" Comment: likely adequate
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Non‐blinded Comment: unclear how this would have influenced results
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Echocardioraphy operators were non‐blinded Quote: "findings reviewed in a non blinded manner" Unclear if laboratory team processing blood samples were blinded Comment: unclear how this would have influenced results
Incomplete outcome data (attrition bias) All outcomes	Low risk	Key outcome variables are reported as per protocol analysis with intention‐to‐treat analysis variable performed
Selective reporting (reporting bias)	Low risk	Published methodology consistent with that reported in published results
Other bias	Low risk	None identified