Perceived food intolerance and irritable bowel syndrome in a population 3 years after a giardiasis-outbreak: a historical cohort study

Table 1 Characteristics of 817 Giardia exposed and 1128 controls in Bergen, Norway 3 years after outbreak of Giardia-epidemic in 2004

Characteristic	Exposed N = 817		Controls N = 1128		P
	N	%	N	%
Age groups, years					0.107
0–19	39	4.8	36	3.2
20–39	526	64.4	736	65.2
40–59	187	22.9	276	24.5
60–79	56	6.9	76	6.7
80–99	9	1.1	4	0.4
Females	540	66.1	738	65.4	0.772
Marital Status					0.003
Single	271	33.5	293	26.1
Married	497	61.4	778	69.3
Divorced/separated	33	4.1	41	3.7
Widow/widower	9	1.1	11	1.0
Education					0.004
Primary school	37	4.7	59	5.3
Secondary school	169	21.3	308	27.7
University	587	74.0	746	67.0
Source of income					<0.001
Working	576	71.1	881	78.7
Out of Work	70	8.6	96	8.6
Student	137	16.9	121	10.8
Other	27	3.3	22	2.0
Student autumn 2004					<0.001
No	503	62.7	842	75.8
Yes, full time	261	32.5	229	20.6
Yes, part time	38	4.7	40	3.6
IBS	355	46.1	155	14.0	<0.001

Abbreviations: IBS Irritable Bowel Syndrome, P P-value from Pearson’s chi square (exact)

ISSN: 1471-230X