Kao 2012

Methods	Cluster randomised controlled trial.
Participants	Inclusion criteria: adults verbally complaining of knee pain or muscle weakness in lower extremity or when they were confirmed by a clinical examination as having OA affecting their knees. Diagnosis of OA of the knee confirmed by medical history and a physical examination. Consisted of having at least 1 of 3 conditions: aged > 50 years; having morning stiffness lasting for < 30 minutes or existing crepitus when moving the legs; or an X‐ray showing osteophytes. Exclusion criteria: previous knee replacement or surgery, unable to maintain balance while standing independently, comorbidity with any medical conditions that could be exacerbated by the protocol, such as unstable heart disease. Country: Taiwan. Sample number: IG: 114; CG: 91. Mean age: 67 years. Progress Plus: gender: mixed; marital status: single/widow: 34.2%, married: 65.8%; elementary/primary school education: 41.2%, high school education: 28.1%, above college education: 30.7%.
Interventions	Provider(s): physical therapist. Training: yes. Setting: community. Content: education; stretching and strengthening exercises and discussion. Length/intensity: 80‐minute sessions 1 × week for 4 weeks. Control: Normal routine care.
Outcomes	At 8 weeks: pain (HRQoL); function (HRQoL); SF‐36: mental health; social function; emotional role, vitality.
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Lack of information regarding cluster randomisation process.
Allocation concealment (selection bias)	High risk	No information.
Blinding of participants and personnel (performance bias) All outcomes	High risk	Not reported, but unlikely that providers and participants were blind to treatment condition.
Blinding of outcome assessment (detection bias) All outcomes	High risk	Unblinded outcomes assessors.
Incomplete outcome data (attrition bias) All outcomes	High risk	Attrition: IG: 14.9% (20/134); CG: 27.2% (34/125). Details of how missing data were handled not reported. No ITT analysis.
Selective reporting (reporting bias)	Low risk	Selective outcome not apparent.
Other bias	Low risk	No other bias detected.