IMPACT 2016.

Methods	Randomized open‐label one‐way cross‐over RCT. Follow‐up: until 12 months, but only three‐month results published at time of review.
Participants	Baseline Age: treatment 64 years versus control 63 years Participants: treatment n = 43 versus control n = 50 % female: 61% Disease distribution: homogenous Baseline score on outcomes: Mean FEV1 % predicted (SD): treatment 28.4% (6.3) versus control 29.9% (6.6) Mean QoL in units total score on SGRQ (SD): treatment 63.2 units (13.7) versus control 59.3 units (15.6) Mean RV % predicted (SD): treatment 277.3% (55.2) versus control 273.7% (63.4) Mean TLC % predicted (SD): treatment 144.9% (21.2) versus control 144.2% (17.6) Mean DLCO % predicted (SD): not reported Mean PaO2 in mm Hg (SD): not reported Mean PaCO2 in mm Hg (SD): not reported Mean 6MWD in meters (SD): treatment 308 m (91) versus control 328 m (93)
Interventions	Intervention: Endobronchial valves Control: optimal medical care
Outcomes	‐ Forced expiratory volume in one second (FEV1) ‐ St. George Respiratory Questionnaire (SGRQ) ‐ Residual volume (RV) ‐ 6‐minute walking distance (6MWD) ‐ Modified Medical Research Council (mMRC) dyspnoea score ‐ CAT score ‐ BODE index
Notes	"This study was sponsored and funded by Pulmonx Corporation, Redwood City, CA, USA"
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Randomization used a blocked design, although a change in randomization blocks happened during the trial
Allocation concealment (selection bias)	Low risk	Concealed envelopes were used
Blinding of participants and personnel (performance bias) All outcomes	High risk	Open‐label trial
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Not mentioned
Incomplete outcome data (attrition bias) All outcomes	Low risk	Well documented reasons for exclusion, drop‐outs and adverse events
Selective reporting (reporting bias)	Low risk	NCT02025205 ‐ reported all outcomes
Other bias	Low risk	None found