Table 3.

Subjects with at least one GI symptom, divided by age groups^a

Age Groups		Morning only	Shift working	Total
20-29	positive	1	38	39
	negative	2	2	10
30-39	positive	13	58	71
	negative	8	8	16
40-49	positive	1	13	14
	negative	1	8	9
50<	positive	1	0	1
	negative	0	0	0

^a p = 0.015, tested by Fisher exact test.