Fig. 1.

Sample selection of patients with IBD and without IMD. IBD inflammatory bowel disease, IMD immune-mediated disease. ^aIMD included ankylosing spondylitis, atopic dermatitis, inflammatory bowel disease, multiple sclerosis, plaque psoriasis, psoriatic arthritis, rheumatoid arthritis and systemic lupus erythematosus. ^bQualifying diagnoses were identified on the inpatient and/or outpatient services claims datasets. ^cFor patients with ≥ 1 IMD, the index date was the day after a randomly selected date of a claim for an IMD. For patients without IMD, the index date was the day after a randomly selected date of a claim. ^dThe baseline period was the 12-month period prior to the index date