Table 2.

Predefined Algorithm to Identify Hospitalized GI Perforation Cases

				Total Identified GI Perforation Cases in Claims Dataa (n = 704)	GI Perforation Cases Included in Validation Sampleb (n = 92)			PPV
					Total	Confirmed	Unconfirmed
GI Site	ICD-9-CM Diagnosis Code		CPT-4 Procedure Code	n	n	n	n	%
Esophagus	530.4			28	5	5	0	100
Stomach	531.1			22	2	2	0	100
	531.2			1	0	0	0	N/A
	531.5			78	8	8	0	100
	531.6			7	1	1	0	100
	532.1			23	2	2	0	100
	532.2			2	0	0	0	N/A
	532.5			70	8	8	0	100
	532.6			9	0	0	0	N/A
	533.1			1	0	0	0	N/A
	533.2			2	0	0	0	N/A
	533.5			7	1	1	0	100
	533.6			0	0	0	0	N/A
Small Intestine	534.1			0	0	0	0	N/A
	534.2			0	0	0	0	N/A
	534.5			5	1	1	0	100
	534.6			0	0	0	0	N/A
	557.0 or 557.1 or 557.9 or 562.0	A	44602 or 44603 or 44120 or 44121 or 44125 or 44130 or 44202 or 44203	0	0	0	0	N/A
		N
		D
Large Intestine	540			130	17	16	1	94.1
	557.0 or 557.1 or 557.9 or 562.1	A	44604 or 44605 or 44140 or 44145 or 44204 or 44205	15	0	0	0	N/A
		N
		D
Unspecified Lower GI	569.83			325	47	42	5	89.4

PPV=Positive Predictive Value

^aGI perforation cases identified from the Premier Inpatient Database and based on the coding algorithm in Appendix.

^bGI perforation cases validated using chart review data based on physicians’ independent review.