Table 1. Characteristics of case and control group.

IBS; irritable bowel syndrome

Characteristics	IBS positive (n = 456)	IBS negative (n = 1,304)	p-value
Gender (%)
Male	175 (38.3)	682 (52.3%)	<0.00001
Female	281 (61.7)	622 (47.7%)
Age in years (%)
18-30	201 (44.0%)	401 (30.7%)	<0.00001
31-40	155 (33.9%)	341 (26.1%)
41-50	100 (21.9%)	562 (43.0%)