Table 4. Hazard ratio (HR) and 95% confidence interval (CI) of cancer mortality according to red meat intake in the HPFS and NHS.

	Frequency of consumption (quintiles)					P for trend	HR (95% CI) for 1 serving/d increase
						P for trend	HR (95% CI) for 1 serving/d increase
	Q1	Q2	Q3	Q4	Q5
HPFS

Total red meat
Cases/person-years	598/152206	558/153082	561/152574	646/153343	710/152584
Age-adjusted model	1.00	1.03 (0.91-1.15)	1.05 (0.93-1.18)	1.20 (1.07-1.34)	1.33 (1.20-1.49)	<0.001	1.17 (1.12-1.22)
Multivariate model^a	1.00	1.05 (0.94-1.18)	1.07 (0.95-1.20)	1.18 (1.05-1.33)	1.24 (1.09-1.40)	<0.001	1.12 (1.06-1.17)
Unprocessed red meat
Cases/person-years	650/151745	588/150121	540/155255	613/152008	682/154661
Age-adjusted model	1.00	1.00 (0.89-1.12)	0.97 (0.86-1.08)	1.06 (0.95-1.18)	1.25 (1.12-1.39)	<0.001	1.18 (1.11-1.26)
Multivariate model^a	1.00	1.01 (0.90-1.13)	1.03 (0.91-1.15)	1.05 (0.94-1.18)	1.18 (1.05-1.33)	<0.001	1.13 (1.05-1.21)
Processed red meat
Cases/person-years	669/172756	487/131895	580/153463	589/153122	748/152551
Age-adjusted model	1.00	0.97 (0.86-1.09)	1.09 (0.98-1.22)	1.09 (0.97-1.21)	1.28 (1.15-1.42)	<0.001	1.31 (1.21-1.41)
Multivariate model^a	1.00	1.00 (0.89-1.12)	1.07 (0.96-1.20)	1.07 (0.95-1.20)	1.15 (1.02-1.29)	<0.001	1.17 (1.07-1.27)

NHS

Total red meat
Cases/person-years	1264/439774	1191/443495	1185/440970	1263/441727	1488/441393
Age-adjusted model	1.00	1.04 (0.96-1.13)	1.08 (1.00-1.17)	1.19 (1.10-1.29)	1.39 (1.29-1.50)	<0.001	1.21 (1.17-1.25)
Multivariate model^a	1.00	1.05 (0.97-1.14)	1.10 (1.01-1.19)	1.15 (1.06-1.25)	1.17 (1.08-1.28)	<0.001	1.09 (1.05-1.13)
Unprocessed red meat
Cases/person-years	1308/442572	1222/442671	1120/440530	1215/432361	1526/449225
Age-adjusted model	1.00	1.02 (0.94-1.10)	0.97 (0.90-1.06)	1.09 (1.01-1.18)	1.33 (1.24-1.44)	<0.001	1.22 (1.17-1.27)
Multivariate model^a	1.00	1.04 (0.96-1.12)	1.03 (0.95-1.12)	1.11 (1.02-1.20)	1.17 (1.08-1.27)	<0.001	1.09 (1.04-1.14)
Processed red meat
Cases/person-years	1294/444119	1230/421760	1236/456687	1204/442791	1427/442002
Age-adjusted model	1.00	1.08 (1.00-1.17)	1.11 (1.03-1.20)	1.14 (1.05-1.23)	1.35 (1.25-1.46)	<0.001	1.41 (1.31-1.52)
Multivariate model^a	1.00	1.05 (0.97-1.14)	1.08 (1.00-1.17)	1.08 (1.00-1.17)	1.14 (1.05-1.23)	0.001	1.14 (1.05-1.24)

Pooled Results^b

Total red meat	1.00	1.05 (0.98-1.12)	1.09 (1.02-1.16)	1.16 (1.08-1.24)	1.19 (1.11-1.28)	<0.001	1.10 (1.07-1.13)
Unprocessed red meat	1.00	1.03 (0.97-1.10)	1.03 (0.96-1.10)	1.09 (1.02-1.16)	1.17 (1.10-1.26)	<0.001	1.10 (1.06-1.14)
Processed red meat	1.00	1.03 (0.97-1.10)	1.08 (1.01-1.15)	1.08 (1.01-1.15)	1.14 (1.07-1.22)	<0.001	1.16 (1.09-1.23)

Abbreviation: HPFS, Health Professionals Follow-up Study; NHS, Nurses' Health Study.

Multivariate model: adjusted for age (continuous), body mass index category (<23, 23-24.9, 25-29.9, 30-34.9, ≥35 kg/m²), alcohol consumption (0, 0.1-4.9, 5.0-14.9, ≥15 g/d), physical activity level (<3, 3-8.9, 9-17.9, 18-26.9, ≥27 hours of metabolic equivalent tasks per week), smoking status (never, past, current 1-14 cigarettes/d, current 15-24 cigarettes/d, current ≥25 cigarettes/d,), race (white/non-white), menopausal status and hormone use in women (premenopausal, postmenopausal never users, postmenopausal past users, postmenopausal current users), family history of diabetes, myocardial infarction, or cancer, history of diabetes, hypertension, or hypercholesterolemia, quintiles of total energy intake, whole grains, fruits, and vegetables.

Results from multivariate model were combined using random-effects model.