Abbink 2004.

Study characteristics
Methods	RCT, parallel group. Setting: Netherlands. Study duration: 12 months
Participants	51 participants Intervention: n = 26, Control: n = 22 Males: n = 37, Female: n = 14 Age, mean: Intervention: 66, Control: 64 FEV1% predicted, mean and SD: Intervention: 34.2 ± 6.4, Control: 32.9 ± 9.0 Inclusion criteria: COPD patients who participated in outpatient PR of 12 weeks. Exclusion criteria: unclear
Interventions	Intervention group Components: not reported Supervision: weekly maintenance programme. Control group: not reported
Outcomes	Exercise capacity: 6MWD, maximal workload on a cycloergometer (watts) and HRQoL: CRQ (global score)
Notes	No study sponsor. It is a conference abstract.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Insufficient information. Reported as randomised, but no further information “COPD patients were randomized to RC or to MP”
Allocation concealment (selection bias)	Unclear risk	Insufficient information. Method of concealment not described.
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Insufficient information.
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Insufficient information.
Incomplete outcome data (attrition bias) All outcomes	High risk	Percentage attrition was higher for intervention group and control group (around 30%).
Selective reporting (reporting bias)	Unclear risk	No paper publication and no information on trial registry.
Other bias	Unclear risk	Any self‐reported outcomes are likely to be affected any bias