Rationale: Hypoxemia associated with acute exacerbations of chronic obstructive pulmonary disease (COPD) often resolves with time. Current guidelines recommend that patients recently discharged with supplemental home oxygen after hospitalization should not have renewal of the prescription without assessment for hypoxemia. Understanding patterns of home oxygen reassessment is an opportunity to improve quality and value in home oxygen prescribing and may provide future targets for deimplementation.Objectives: We sought to measure the frequency of home oxygen reassessment within 90 days of hospitalization for COPD and determine the potential population eligible for deimplementation.Methods: We performed a cohort study of patients ≥40 years hospitalized for COPD at five Veterans Affairs facilities who were prescribed home oxygen at discharge. Our primary outcome was the frequency of reassessment within 90 days by oxygen saturation (Sp_O2) measurement. Secondary outcomes included the proportion of patients potentially eligible for discontinuation (Sp_O2 > 88%) and patients in whom oxygen was discontinued. Our primary exposures were treatment with long-acting bronchodilators, prior history of COPD exacerbation, smoking status, and pulmonary hypertension. We used a mixed-effects Poisson model to measure the association between patient-level variables and our outcome, clustered by site. We also performed a positive deviant analysis using chart review to uncover system processes associated with high-quality oxygen prescribing.Results: A total of 287 of 659 (43.6%; range 24.8-78.5% by site) patients had complete reassessment within 90 days. None of our patient-level exposures were associated with oxygen reassessment. Nearly half of those with complete reassessment were eligible for discontinuation on the basis of Medicare guidelines (43.2%; n = 124/287). When using the newest evidence available by the Long-Term Oxygen Treatment Trial, most of the cohort did not have resting hypoxemia (84.3%; 393/466) and would be eligible for discontinuation. The highest-performing Veterans Affairs facility had four care processes to support oxygen reassessment and discontinuation, versus zero to one at all other sites.Conclusions: Fewer than half of patients prescribed home oxygen after a COPD exacerbation are reassessed within 90 days. New system processes supporting timely reassessment and discontinuation of unnecessary home oxygen therapy could improve the quality and value of care.