Table 2.

Training and Test Set Patient and Surgical Site Infection (SSI) Characteristics

Characteristic	Training set (2011–2012)					Test set (2013)
	ALL Procedure	Overall SSI	Superficial SSI	Deep SSI	Organ Space SSI	ALL Procedure	Overall SSI	Superficial SSI	Deep SSI	Organ Space SSI
Total	2840	252	132	51	81	1651	114	41	34	41
Encounter type
Inpatient	2429	242	129	47	78	1052	104	35	32	38
Outpatient	411	10	3	4	3	599	10	6	2	3
Age group
< 65	2259	210	109	41	67	1269	91	30	28	34
≧65	581	42	23	10	14	382	23	11	6	7
Gender
Male	1246	119	63	22	39	774	51	19	15	18
Female	1594	133	69	29	42	877	63	22	19	23
Race
White	2386	213	112	44	66	1481	99	34	30	38
African American	189	18	8	5	7	112	7	3	1	2
Other/unknown	265	21	12	2	8	58	8	4	3	1