All population i.e. U>U40 years: Each initial maintenance treatment (IMT) cohort (FSC 250/50mcg dose only, IP, and TIO) includes patients aged 40 years and older with at least 9 months of continuous enrollment (6 months pre-index and at least three months post-index) with a primary or secondary diagnosis of COPD [International Classification of Disease, 9th revision, Clinical Modification (ICD-9-CM) codes 491.xx, 492.xx or 496.xx]. Patients are observed such that everyone provides minimum 6 months of pre index baseline data and minimum 3 months post index (risk analysis) and minimum 12 months post index for cost analysis. Patients must receive either a 30-day supply of FSC or IP or TIO as the initial IMT medication, indicating "intent to treat." Patients may not also have a prescription filled for the other IMT medication within 60 days of the index date, or for the combination therapy budesonide/ formoterol (BFC), an inhaled corticosteroid (ICS) or a long acting beta agonist (LABA).