Fig. 17:  This Figure summarizes data on the equipoise that oxygen therapy has on exercise desaturation in COPD.  The table^[1] summarizes the results of several small studies, some double-blind, randomized, controlled trials, some single-blinded randomized controlled trials, and some merely prospective randomized controlled trials.  The various studies looked duration of exercise, change in 6-minute walk test, reduction in dyspnea, or improvement in quality of life, and it can be seen in this aggregate table that in patients who desaturate with ambulation there is no consistent effect of oxygen therapy on improving exercise performance, improving the 6-minute walk test, reducing dyspnea on a reproducible fashion, or improving quality of life.