Park 2014

Methods	Quasi‐experimental partially randomised controlled trial.
Participants	Inclusion criteria: aged > 65 years; living in the community/non‐institutionalised; self‐reported joint pain attributed to OA and in 1 or more of hip, knee, foot or ankle; chronic pain ≥ 15 days a month for > 3 months, pain level ≥ 4 on a 10‐point scale (1 = no pain, 10 = excruciating pain); inability to participate in standing exercise; ability to speak English. Sample size: 34; IG: 23; CG: 11. Mean age: 79 years (SD 6.42). Country: US. Progress Plus: 26 women (76.5%); 21 non‐Hispanic white (61.8%); 19 widowed (55.8%); 27 (79.4%) reported chronic pain for > 3 years; 11 (73.5%) reported highest pain level ≥ 5; 27 (79.4%) taking medication for pain.
Interventions	Providers: Yoga Alliance certified instructors with cardiopulmonary resuscitation certification and ≥ 1 year of yoga teaching experience. Setting: group sessions at a senior centre. Content: chair yoga. Length/intensity: both groups had 45 minutes twice a week for 8 weeks. Control: general health education information and specific facts related to effects of OA.
Outcomes	Outcomes: at 4 and 8 weeks: pain (McGill Pain Questionnaire); gait speed (Gait Speed Test); exercise tolerance (6‐minute walk test); balance (Berg Balance Scale); depression (Geriatric Depression Scale, Short Form); life satisfaction (Life Satisfaction Index for the Third Age).
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	High risk	Sealed envelopes; unclear if these were selected 1 by 1 removed from box: this could have made subsequent participants have an increased chance of picking an envelope for a particular condition.
Allocation concealment (selection bias)	High risk	9 participants with more severe Alzheimer's disease were assigned to the intervention condition as the control condition was not suitable for them.
Blinding of participants and personnel (performance bias) All outcomes	High risk	No blinding apparent, and CG participants appeared to have been aware of what the IG entailed (contamination reported by authors).
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Not described.
Incomplete outcome data (attrition bias) All outcomes	High risk	Attrition: uneven and some uncertainty in reporting. 1 IG (due to unrelated hospitalisation) and 5 CG withdrew (1 due to scheduling and preference for IG, others unspecified. Some inconsistency in reporting: the final reported sample size is "29 participants after 5 participants withdrew" but other reporting suggested 6 withdrawals.
Selective reporting (reporting bias)	Low risk	All measured variables had results reported.
Other bias	Low risk	No other bias identified.