. Author manuscript; available in PMC: 2021 Nov 1.

Published in final edited form as: Clin Pharmacol Ther. 2020 May 31;108(5):1010–1017. doi: 10.1002/cpt.1885

Table 1.

Operational definitions of outcomes of interest and performance measures of the outcome ascertainment algorithms

Outcome	ICD-9-CM code	Description	Diagnosis position and claim type	Performance of algorithm
Gastrointestinal bleeding	530.21	Esophageal ulcer, with hemorrhage	Any position of discharge diagnosis in inpatient claims	PPV ~81%²⁸
	531.0X, 531.2X, 531.4X, 531.6X	Gastric ulcer, with hemorrhage
	532.0X, 532.2X, 532.4X, 532.6X	Duodenal ulcer, with hemorrhage
	533.0X, 533.2X, 533.4X, 533.6X	Peptic ulcer, with hemorrhage
	534.0X, 534.2X, 534.4X, 534.6X	Gastrojejunal ulcer, with hemorrhage
	535.01, 535.11, 535.21, 535.31, 535.41, 535.51, 535.61, 535.71	Gastritis and duodenitis, with hemorrhage
	537.83, 537.84	Other specified disorder of stomach and duodenum, with hemorrhage
	562.02, 562.03, 562.12, 562.13	Diverticula of intestine, with hemorrhage
	569.85, 569.86	Other disorders of intestine, with hemorrhage
	578.X	Gastrointestinal hemorrhage
Non-traumatic intracranial hemorrhage	430	Subarachnoid hemorrhage	Any position of discharge diagnosis in ED or inpatient claims, excluding cases with traumatic brain injury diagnosis (ICD-9-CM codes 800–804, 850–854) in any position on the same admission date	PPV ~98% (subarachnoid hemorrhage), ~97% (intracerebral hemorrhage)²⁹
Non-traumatic intracranial hemorrhage	431	Intracerebral hemorrhage

ED: emergency department. ICD-9-CM: International Classification of Diseases, 9th Revision, Clinical Modification. PPV: positive predictive value.