Table 1.

Comparison of subjects with IBS and controls by demographic variables

		IBS n (%)	Controls n (%)
Gender	Male	27 (15)	9 (18)
	Female	159 (85)	41 (82)
Race	White only	153 (82)	40 (80)
	African American only	7 (4)	1 (2)
	Asian only	7 (4)	1 (2)
	American Indian/Alaskan Native only	1 (1)	0
	Native Hawaiian/Pacific Islander only	0	0
	More than one race	17 (9)	5 (10)
	Unknown	1 (1)	3 (6)
Age		44.6 ± 14.2	43.9 ± 14.8

Note: For categorical variables (gender and race) the numbers (n) and the percentages (%) of subjects with IBS (n = 186) and controls (n = 50) that met the demographic criteria listed are given. For age, mean ± SD is given. Differences between subjects with IBS and controls were not significant (Fisher's exact test or two-sample t-test)