TABLE I.

Basic demographics of cases of anaphylaxis

	Northern United States (11 hospitals)		Southern United States (13 hospitals)
	Absolute no.	Rate (per 1,000)	Absolute no.	Rate (per 1,000)	P value
Cases of anaphylaxis	3,704	0.88	2,753	0.63	<.001
Total patient visits	4,199,103		4,390,480
Median age (y)	4.3		4.0
Sex
Male (cases)	2,018	0.90	1,453	0.61	<.001
Total visits	2,244,487*		2,372,381*
Female (cases)	1,686	0.86	1,300	0.64	<.001
Total visits	1,954,393*		2,018,075*
Race/ethnicity
White/non-Hispanic (cases)	2,285	1.06	1,072	0.87	<.001
Total visits	2,159,145		1,230,543
Black (cases)	671	0.62	924	0.56	.044
Total Visits	1,082,313		1,650,409
Hispanic (cases)	207	0.52	475	0.44	.045
Total visits	401,791		1,089,432
Asian (cases)	114	2.11	38	0.75	<.001
Total visits	53,943		50,809
Native American (cases)	7	0.77	2	0.76	.991
Total visits	9,113		2,627
Other (cases)	249	0.87	145	0.71	.054
Total visits	285,845		203,651
Unknown (cases)	171	0.83	97	0.60	.010
Total visits	206,953		163,009
Patient location
Emergency department (cases)	2,640	0.78	1,725	0.49	<.001
Total visits	3,395,655		3,524,166
Inpatient (cases)	1,064	1.32	1,028	1.19	.012
Total visits	803,448		866,314

^*There were 24 visits in the south and 223 visits in the north without a sex listed.