. Author manuscript; available in PMC: 2014 Feb 6.

Published in final edited form as: J Endometr. 2013 May 2;5(1):17–26. doi: 10.5301/je.5000151

TABLE III.

MULTIVARIABLE RATE RATIOS (RR) AND 95% CONFIDENCE INTERVALS (CIs) FOR LAPAROSCOPICALLY-CONFIRMED ENDOMETRIOSIS (N = 1383) ACCORDING TO QUINTILE OF CUMULATIVE AVERAGED MICRONUTRIENT INTAKE FROM SUPPLEMENTS ALONE AMONG WOMEN IN THE NURSES’ HEALTH STUDY II, 1991–2007

	Quintile of Intake
	1	2	3	4	5	P-value^*
Thiamine (B₁)	1.00 (referent)	1.17 (0.87, 1.56)	1.13 (0.84, 1.54)	1.20 (0.89, 1.61)	1.22 (0.91, 1.65)	0.34
Niacin (B₃)	1.00 (referent)	1.15 (0.85, 1.54)	1.08 (0.79, 1.46)	1.23 (0.91, 1.65)	1.23 (0.91, 1.66)	0.15
Pyridoxine (B₆)	1.00 (referent)	0.97 (0.81, 1.15)	1.03 (0.87, 1.22)	1.07 (0.91, 1.26)	1.00 (0.84, 1.18)	0.91
Folate (B₉)	1.00 (referent)	1.33 (0.98, 1.80)	1.20 (0.87, 1.65)	1.36 (1.00, 1.84)	1.27 (0.94, 1.72)	0.91
Cobalamine (B₁₂)	1.00 (referent)	1.00 (0.85, 1.19)	1.08 (0.91, 1.28)	1.16 (0.98, 1.38)	1.00 (0.85, 1.20)	0.87
Vitamin C	1.00 (referent)	1.07 (0.87, 1.31)	1.01 (0.83, 1.24)	1.01 (0.83, 1.23)	1.16 (0.95, 1.41)	0.14
Vitamin E	1.00 (referent)	1.08 (0.88, 1.34)	1.10 (0.89, 1.35)	1.00 (0.82, 1.23)	1.21 (0.99, 1.48)	0.04
	Frequency of Multivitamin Use
		None	0–2 per wk	3–5 per wk	>5 per wk
Multivitamins		1.00 (referent)	0.93 (0.79, 1.11)	0.97 (0.84, 1.13)	1.08 (0.94, 1.23)	0.34

P-value, test for linear trend calculated with median intake of the micronutrient in each quintile as a continuous variable.

⁺

Multivariable model was stratified by age in months at start of follow-up and calendar year of the current questionnaire cycle and was simultaneously adjusted for age at menarche (<10, 10, 11, 12, 13, 14, 15, 16, >16 years), length of menstrual cycle (<26, 26–31, 32–50, 51+ days), parity (nulliparous, 1, 2, 3, 4+ pregnancies lasting >6 months), body mass index (<19, 19–20.4, 20.5–21.9, 22–24.9, 25–29.9, 30+ kg/m²), race (Caucasian vs. women of color), and total energy (continuous).

CI, confidence interval; RR, rate ratio.