Selection criteriaOnly randomized c

Selection criteria
Only randomized controlled trials (RCTs) comparing oxygen-supplemented exercise training to non-supplemented exercise training
(control group) were considered for inclusion. Participants were 18 years or older, diagnosed with COPD and did not meet criteria for
long-term oxygen therapy. No studies with mixed populations (pulmonary fibrosis, cystic fibrosis, etc) were included. Exercise training
was greater than or equal to three weeks in duration and included a minimum of two sessions a week.