Iwamoto 2009.

Methods	Study design: RCT Number of study arms: 2 Length of follow‐up: 5 months
Participants	Setting: Tokyo, Japan Number of participants: 68 Number analysed: 67 Number lost to follow‐up: 1 Sample: volunteer patients from Department of Orthopaedic Surgery (2 hospitals) and Orthopaedic Clinics (3) Age (years): mean 76.4 (SD 5.6), range 66 ‐ 88 Sex: 90% female Inclusion criteria: aged > 50 years; fully ambulatory; able to complete physical assessments Exclusion criteria: using walking aids; severe kyphosis due to osteoporotic vertebral fractures; acute illness; severe cardiovascular disease
Interventions	1. Group‐based balance and gait training: supervised exercise programme (calisthenics, balance, muscle power, walking ability training); 30 minutes, 3 a week for 20 weeks 2. Control group: no exercise
Outcomes	1. Number of people who experienced 1 or more falls (risk of falling)
Duration of the study	20 weeks
Adherence	Adherence not defined. Completion rate: 1. Group‐based balance and gait training group: all participants completed the 5‐month trial; adherence not defined 2. Control group: 33/34 participants completed trial
Notes	Source of funding: Keio University School of Medicine Economic information: not reported Place of residence not specified, i.e. not specifically community‐dwelling, but not preventing falls in hospital or specifically in an institution
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Quote: "The subjects were randomly divided into two groups ..."
Allocation concealment (selection bias)	Unclear risk	Quote: "The subjects were randomly divided into two groups ..."
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Participants and personnel unblinded but impact of unblinding unknown
Blinding of outcome assessment (detection bias) Falls	High risk	Assessor blinding is unclear, but assume obtaining "information regarding falls and fractures .... every week by directly asking the participants" occured for exercise participants during class and control participants were assessed at 2½ and 5 months
Blinding of outcome assessment (detection bias) Fractures	High risk	Fractures appear to be self‐reported with no confirmation from medical records
Blinding of outcome assessment (detection bias) Hospital admission, medical attention and adverse events	Unclear risk	Method of ascertaining adverse events unclear
Blinding of outcome assessment (detection bias) Health related quality of life (self report)	Unclear risk	Not applicable
Incomplete outcome data (attrition bias) Falls and fallers	Low risk	Less than 20% of fall outcome data are missing (2%). Only missing data are from 1 control participant due to noncompliance
Selective reporting (reporting bias)	High risk	Falls were measured, but number of fallers not reported
Method of ascertaining falls (recall bias)	High risk	Quote: "The incidence of fall and fracture … was assessed 2.5 and 5 months after the start of the trial. In particular, information regarding falls and fractures was obtained every week by directly asking the participants." No mention of diaries or calendars. Retrospective recall. Possibly only the intervention group were asked every week (at class) and remainder at 2½ and 5 months.