Table 2

Odds ratios of cancer of the colorectum, colon, or rectum for quartiles of serum IGF-1 and IGFBP-3

	Quartile level
	1	2	3	4	p for trend
Conditional logistic regression analyses were matched for age, sex, date of blood sampling, and fasting status, and further adjusted for smoking status.
OR, odds ratio; CI, confidence interval; IGF-I, insulin-like growth factor 1; IGFBP, IGF binding protein.
Colorectum: IGF-1 measurements were missing for one control; IGFBP-3 measurements were missing for one case and one control.
Rectum: IGF-1 measurements were missing for one control; IGFBP-3 measurements were missing for one case and one control.
Cut off points: IGF-1, 146.35–197.59–252.64; IGFBP-3, 2176–2575–2948.
IGF-1
Colorectum
OR	1.00	1.17	1.19	1.27	0.51
95% CI	—	0.66–2.08	0.63–2.22	0.65–2.47
No of cases/controls	39/86	43/83	45/81	41/85
Mean exposure	109.86	172.71	222.79	293.14
Colon
OR	1.00	1.89	2.30	2.66	0.03
95% CI	—	0.89–4.04	1.02–5.17	1.09–6.50
No of cases/controls	21/64	30/57	30/46	29/53
Mean exposure	105.92	172.71	222.59	293.54
Rectum
OR	1.00	0.45	0.33	0.33	0.09
95% CI	—	0.13–1.53	0.09–1.14	0.09–1.13
No of cases/controls	18/22	13/26	15/35	12/32
Mean exposure	118.24	172.72	223.11	292.41

IGFBP-3
Colorectum
OR	1.00	0.80	1.25	1.23	0.24
95% CI	—	0.44–1.45	0.68–2.29	0.68–2.22
No of cases/controls	40/85	35/91	46/79	46/80
Mean exposure	1754	2394	2740	3456
Colon
OR	1.00	0.91	1.80	1.93	0.02
95% CI	—	0.42–1.94	0.82–3.98	0.92–4.06
No of cases/controls	23/55	23/64	30/50	34/51
Mean exposure	1761	2405	2738	3457
Rectum
OR	1.00	0.75	0.66	0.49	0.21
95% CI	—	0.27–2.06	0.23–1.87	0.16–1.49
No of cases/controls	17/30	12/27	16/29	12/29
Mean exposure	1743	2370	2743	3459