Thom 2018.

Study characteristics
Methods	Design: single blind RCT Duration: 39 weeks Location: USA Setting: 7 urban, county‐operated primary care clinics, including 2 academic residency teaching practices, that primarily serve a low‐income, publicly insured patient population
Participants	Population: 192 adults with COPD randomised to receive 39 weeks of health coaching (n = 100) or usual care (n = 92) Baseline characteristics COPD severity: moderate to severe Age (mean): intervention 60.7 (SD 8.0) years; control 61.9 (SD 7.2) years % males: intervention 67%; control 64.1% FEV1 % predicted (mean): intervention 55% (SD 19%); control 60% (SD 20%) High COPD symptom score: CAT ≥ 10: intervention 90.9%; control 94.6% Inclusion criteria: moderate‐to‐severe COPD, confirmed by a postbronchodilator FEV1:FVC ratio < 0.70 or by review by a pulmonologist Exclusion criteria: unable to participate in the study due to mental or physical impairment, severe or terminal illness that precludes focus on COPD, no telephone (from protocol)
Interventions	Treatment arms Health coaching intervention Usual care (any standard care provided by clinic, which were included but not limited to visits with the primary care clinician, pulmonary clinician or both, COPD education, pulmonary rehabilitation, smoking cessation resources) Allowed co‐medications: SABA, SAAC, LABA, LAMA, ICS
Outcomes	Primary outcomes: COPD‐related quality of life on the CRDQ‐ SF scale: total and dyspnoe domain Secondary outcomes: rate of COPD exacerbations per year, excercise capacity (6MWT), Self‐efficacy to Manage Chronic Disease Scale Additional outcomes: SF PACIC, CAT, FEV1 (% predicted), percentage of participants reporting current cigarette use, COPD‐related function (bed days due to respiratory problems), percentage of people demonstrating adequate inhaler use (as a measure of adherence); self‐reported adherence to inhaled controller medications in the past 7 days and observed technique, percentage of people with correct answer to knowledge questions 1 to 4, rates of outpatient visits, ED visits and hospitalisations (non‐COPD and COPD‐related)
Notes	Funding: Patient‐Centered Outcomes Research Institute (PCORI AD‐1306‐03900) and supported by the NIH/NCRR Colorado CTSI (grant number UL1 RR025780) Identifiers: NCT02234284
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Random binary sequence created by the project manager and stratified by site.
Allocation concealment (selection bias)	Low risk	Sequentially numbered envelopes were used to mask allocation.
Blinding of participants and personnel (performance bias) all outcomes	High risk	Single blind; participants were aware of assignment and reported adherence.
Blinding of outcome assessment (detection bias) all outcomes	Low risk	Quote: "Study investigators and data safety monitoring board were blinded to assignment until analyses were finalised."
Incomplete outcome data (attrition bias) all outcomes	High risk	Higher attrition in the intervention group (29%) vs usual care (14%); ITT was implemented; however, adherence outcome was based on number of 98 instead of 138. It is unclear if imputation is based on such low sample sizes/information.
Selective reporting (reporting bias)	High risk	The trial was registered on website; however, there were some inconsistencies of reporting of outcomes between the protocol and the publication. For example, number of days (of the last 7) participants reported taking medications as prescribed (measured by % adherence), which was not mentioned in the protocol but was reported in the publication. Morisky Adherence Scale was planned in the protocol but was deleted from the findings because of licence issues.
Other bias	Unclear risk	Participants received up to USD 30 at baseline and USD 60 at 9 months for acknowledgement of participation.