Colon cancer controls versus population controls in case-control studies of occupational risk factors

BMC Cancer

Table 2 Odds ratios for demographic, life style and medical characteristics in colon cancer controls compared with population controls

	Colon cancer controls (N = 254)		Population controls (N = 320)		Crude OR	Adjusted OR²	95% CI²
	No.	%	No.	%
Educational status, low³	59	23	89	28	0.8	0.7	0.5–1.0
Living alone	43	17	77	24	0.7	0.6	0.4–0.9
Ever smokers	180	71	228	71	1.0	1.0	0.7–1.4
Heavy smokers⁴	70	28	88	28	1.0	0.9	0.7–1.3
Alcohol, high⁵	108	43	98	31	1.7	1.8	1.2–2.5
-Age 35–59	48		59		1.3	1.3	0.8–2.2
-Age 60–69	60		39		2.3	2.3	1.4–3.9
Obesity⁶	51	20	53	17	1.4	1.4	0.9–2.2
Asthma	15	6	28	9	0.7	0.6	0.3–1.2
Dermatitis	47	19	62	19	0.9	0.9	0.6–1.4

¹ Crude odds ratio (OR). ² OR with 95 % confidence interval (CI), adjusted for sex and age. If expected values were less than 5, Fishers exact test was used with stratification by year of birth (2 levels) and sex. ³ Left school at 15 y no further education. ⁴ More than 20 pack-years ('pack-years' = number of years as a smoker * number of cigarettes per day/20). ⁵ Total alcohol intake > 24 grams alcohol per day. ⁶ Obesity defined as maximum body mass index ever being ≥ 30.

ISSN: 1471-2407