Table 2.

Baseline characteristics for categorical variables by frequency of weekly fish consumption, %.

	n/Total 1	Never	Less than Once	Once	2–3 or More	p 1
Fatty fish consumption
Females	10,269/19,822	11.2	53.5	29.2	6.0	<0.0001
Males	9553/19,822	9.6	51.6	30.4	8.3	<0.0001
Higher education 2	8610/19,773	10.5	57.2	27.4	4.9	<0.0001
Physical activity 3	6670/19,717	10.1	53.5	29.7	6.7	0.2
Smoking	7345/19,802	12.1	50.9	29.3	7.7	<0.0001
Cod liver oil 4	6283/18,746	8.5	49.5	33.3	8.8	<0.0001
Lean fish consumption
Females	10,791/20,806	2.5	19.6	48.1	29.9	<0.0001
Males	10,015/20,806	2.7	19.9	45.2	32.2	<0.0001
Higher education 2	8910/20,747	3.0	22.8	49.3	24.9	<0.0001
Physical activity 3	6958/20,687	2.6	19.8	48.7	28.9	<0.0001
Smoking	7675/20,789	3.1	21.1	45.2	30.5	<0.0001
Cod liver oil 4	6590/19,547	1.9	16.3	47.9	33.9	<0.0001
Processed fish consumption 5
Females	10,578/20,210	4.3	26.8	55.1	13.8	<0.0001
Males	9632/20,210	7.3	34.3	49.1	9.4	<0.0001
Higher education 2	8762/20,153	6.6	28.9	52.6	11.8	<0.0001
Physical activity 3	6799/20,099	6.3	29.7	53.1	11.0	<0.01
Smoking	7460/20,194	6.3	31.9	50.4	11.4	<0.0001
Cod liver oil 4	6424/19,106	5.1	29.3	53.5	12.1	0.001

Numbers of participants vary because of missing information variables. ¹ p-value derived using Chi-square tests with fatty, lean and processed fish consumption as categorical variables (never, <1, 1, 2–3 or more); ² Higher education: High school diploma or more; ³ Average of three or more hours of vigorous leisure time hard physical activity per week (sweating/out of breath once a week or more) during the last year; ⁴ Cod liver oil/fish oil capsules used past 14 days; ⁵ Fish balls/fish pudding/fish cakes. The Tromsø Study: Tromsø 4.