Wu 2017.

Study characteristics
Methods	Study design: RCT Study grouping: parallel‐group
Participants	Baseline characteristics IMT (Threshold device) N (randomized/analyzed): 19/19 Loss to follow‐up or excluded: 0 Age, mean (SD) in years: 59.74 (6.14) BMI, mean (SD), kg/m²: 18.40 (2.19) IMT (resistive device) N (randomized/analyzed): 21/21 Loss to follow‐up or excluded: 0 Age, mean (SD) in years: 62.24 (7.36) BMI, mean (SD), kg/m²: 19.25 (2.17) Control/sham N (randomized/analyzed): 20/29 Loss to follow‐up or excluded: 0 Age, mean (SD) in years: 60.30 (6.55) BMI, mean (SD), kg/m²: 18.54 (2.58) Overall N (randomized/analyzed): 60/60 Loss to follow‐up or excluded: 0 COPD stage (GOLD): moderate to severe Included criteria Moderate, severe and very severe COPD (post‐bronchodilator FEV1/FVC < 70% and FEV1 < 50% of predicted (GOLD B, C and D, respectively) Inspiratory muscle weakness (PImax < 60 cm H2O) Bronchial dilation test (BDT) negative No history of PR Excluded criteria Time from most recent exacerbation > 2 months With no medication changes in 1 month prior to enrollment Obesity (BMI > 30 m2/kg) Severe orthopedic problems having a major impact on ADL Previous inclusion in a rehabilitation program (< 1 year) Concomitant heart failure and pulmonary vascular diseases Diagnosed psychiatric or cognitive disorder Progressive neurological or neuromuscular disorder
Interventions	Intervention characteristics IMT: participants trained twice a day, 15 min/session for 8 weeks using either Threshold IMT (Respironics Inc; Pittsburgh, PA, USA) or Pflex (Respironics Inc, Pittsburgh, PA, USA) devices set at 60% of PImax Control/sham: no intervention received by this group
Outcomes	Dyspnea: BDI‐TDI Functional impairement  Magnitude of task Magnitude of effort Focal score Functional exercise capacity: Wmax (Incremental cycle ergometer test: measured by increasing the work rate by 10 w/min after one minute of unloaded pedalling) Exercise time (Incremental cycle ergometer test) HRQoL: CRQ Dyspnea Fatigue Emotion Mastery Total Respiratory muscle strength: PImax (RV) Laboratory exercise test: VO2peak (L/min) (Incremental cycle ergometer test)  Respiratory function: FEV1 L %pred
Identification	Sponsorship source: the study was supported by the Science and Technology Project of Guangdong Province (2017A020211018) and the Guangzhou Healthcare collaborative innovation major project (201604040012) and State's Key Project of Research and Development Plan(2017YFSF11078). Country: China Setting: Guangzhou Institute of Respiratory Disease Author's name: Rongchang Chen Institution: Guangzhou Institute of Respiratory Disease, State Key Laboratory of Respiratory Disease Email: chenrc_vip@163.com Address: Guangzhou, China Clinical trial register: NCT03101774
Notes