TABLE 1.

Age and sex distribution of inflammatory bowel disease (IBD) respondents

	Crohn disease	Ulcerative colitis
Total respondents*	179 (65)	93 (34)
Male	41 (23)	24 (26)
Female	138 (77)	69 (74)
Age at onset, years
0–19	14 (8)	3 (3)
20–29	38 (21)	32 (34)†
30–39	56 (31)	23 (25)
40–49	37 (21)	18 (19)
50–59	27 (15)	14 (15)
60–69	7 (4)	3 (3)
Age at onset, years, mean (95% CI)	20.6 (19.0–22.2)	26.6 (24.3–29.0)†
Age at diagnosis, years, mean (95% CI)	26.5 (24.8–28.1)	29.4 (27.0–31.9)†
Interval, diagnosis–onset, years, mean (95% CI)	5.9 (4.8–6.9)	2.9 (2.0–3.7)‡

Data presented as n (%) unless otherwise indicated.

^*Individuals with IBD unclassified were not included in this analysis. Different from Crohn disease at

^†P<0.05;

^‡P<0.001