REgistry-based randomized controlled trial of treatment and Duration and mortality in long-term OXygen therapy (REDOX) study protocol

Long-term oxygen therapy (LTOT) during 15 h/day or more prolongs survival in patients with chronic obstructive pulmonary disease (COPD) and severe hypoxemia. No randomized controlled trial has evaluated the net effects (benefits or harms) from LTOT 24 h/day compared with 15 h/day or the effect in conditions other than COPD.