Nguyen 2008.

Study characteristics
Methods	Study design: multi centre, single‐blinded, parallel randomised controlled trial in the USA. Duration: 26 weeks (but study ended early) Setting: secondary care
Participants	Population: 50 adults recruited from two academic medical centres at the University of San Fransisco and University of Washington Baseline characteristics: mean age 70 years, male: 56%, current smokers (n): 3/39, FEV1 (% predicted): 53, concomitant medications: oxygen therapy (11/39), moderate to severe COPD, ethnicity: Caucasian, exacerbations in the last 12 months: NR, cognitive function: NR (but 59% had intermediate computer or Internet skills) Inclusion criteria: COPD diagnosis, clinically stable, FEV1/FVC < 70% and FEV1 < 80% predicted after bronchodilator, activities of daily living limited by dyspnoea, English speaking, able to use computer, oxygen saturation > 85% on < 6L/min nasal oxygen during six‐minute walk test (6MWD), able to rate shortness of breath during exercise, moderate to severe COPD, Exclusion criteria: Other active illness, formal pulmonary rehabilitation training in last six months
Interventions	Measurements taken at baseline, 3 months and 6 months Treatment arms: Internet‐based dyspnoea self‐management programme Usual care (face‐to‐face personalised dyspnoea and exercise plan, and self‐monitoring)
Outcomes	Quality of life (SF‐36 sub scales, CRQ sub scales) Physical activity (6MWD, endurance, strengthening, stage of readiness for exercise) Patient satisfaction Impact on health behaviours (dyspnoea knowledge scale) Exacerbations
Notes	Funding: Robert Wood Health e‐Technologies Initiative grant, General Clinical Research at University of Washington, UC San Fransisco, National Centre for Research Resources Other identifiers: NCT00102401
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Randomisation was achieved by generating a random sequence using a computer program
Allocation concealment (selection bias)	Low risk	Allocation was concealed in sealed opaque envelopes
Blinding of participants and personnel (performance bias) All outcomes	High risk	The study nurse opened the randomisation envelope in the first half of the visit as a requirement due to registering the participant to access web questionnaires. The participants were not informed of their assignment until the visit was complete
Blinding of outcome assessment (detection bias) All outcomes	High risk	Subjective outcomes such as QOL, self‐efficacy and participant satisfaction likely to be high risk as they are self‐reported outcomes
Incomplete outcome data (attrition bias) All outcomes	High risk	Higher attrition percentage in the eDSMP group compared with fDSMP group due to unable or unwilling to access the website or use PDA, scheduling conflict, recurrent angina, or moved away from the area. Outcomes are reported at multiple time points, and high attrition rates may affect outcome data
Selective reporting (reporting bias)	Low risk	All outcomes reported as planned in the protocol on clinicaltrials.gov website. Study was stopped early but not reported when it was terminated
Other bias	Low risk	None identified