Hashizume 1991.

Methods	Method of randomisation: States randomised into 2 groups stratified by age and sex Assessor blinding: No Intention‐to‐treat: Yes
Participants	Location: University School of Medicine, Matsumoto, Japan Period of study: Before April 1991 Participant description: Initial episode of Graves' disease, recruited from OPD endocrine clinic. Diagnosis on basis of TFTs, absence of nodules by palpitation, Diffuse increased uptake on I123 thyroid scan Inclusion criteria: Graves' disease as above Exclusion criteria: Not mentioned Sex: M/F: A: 14/46; B: 10/39 Age: mean (SD) 39(11) years Baseline comparability: Comparable thyroid functions and TRAb levels. No statistically significant differences
Interventions	Description of intervention: All participants received methimazole (MMI) 10 mg t.d.s. for 6 months then divided into 2 groups; 1: TRAb > 15%, 2: TRAb < 15%. Then randomised into 2 groups A: MMI 10mg with thyroxine 100 µg per day Duration of therapy: 12 months then thyroxine alone for a further 3 years B: MMI 10 mg per day with placebo Duration of therapy: 12 months, then placebo alone for a further 3 years
Outcomes	Main outcome: Relapse of hyperthyroidism
Study details	A: MMI 10mg with thyroxine 100 µg per day Duration of therapy: 12 months then thyroxine alone for a further 3 years B: MMI 10 mg per day with placebo Duration of therapy: 12 months, then placebo alone for a further 3 years Allocated: A: 60; B: 49 Completed: A: 60; B: 49 Assessed: A: 60; B: 49 Length of follow‐up: 3 years after MMI therapy
Publication details	Language of Publication: English Publication status: Peer reviewed journal
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Blinding? All outcomes	Low risk
Incomplete outcome data addressed? All outcomes	Low risk