Table 2

Distribution of socio-demographic and cervical neoplasia risk factor characteristics by tertiles of dietary intake and circulating measures among study participants

TertilesDietary food intakePlasma levels
Folate (μg/day)Vitamin B12 (μg/day)Folate (ng/ml)Vitamin B12 (pg/ml)
123123123123
No.7766586578585052677451 45
Age (yr), mean (SD)a24 (4)25 (4)23 (4)24 (4)24 (4)23 (4)23 (4)25 (5)24 (5)25 (4)24 (5)23 (5)
Race (%)b
 Caucasian85.784.965.586.279.572.472.084.680.687.868.677.8
 Hispanic9.110.629.37.716.722.422.011.516.49.523.520.0
 Other5.24.65.1c6.23.95.26.03.93.02.77.82.2c
Education (% ≥some college)b70.168.277.673.971.869.066.067.377.674.329.433.3
Marital status (%)b
 Single64.972.774.164.674.470.760.067.373.166.270.666.7
 Married11.77.65.210.811.51.714.07.74.510.85.96.7
 Cohabiting7.812.115.510.87.717.214.013.511.914.913.78.9
 Divorced/separated15.67.65.213.96.410.312.011.510.58.19.817.8
BMI, mean (SD)a23.8 (5.5)23.6 (5.2)22.8 (4.5)23.5 (5.2)23.6 (5.1)23.1 (5.3)24.3 (6.1)23.3 (4.2)22.9 (5.6)23.3 (5.1)24.0 (6.4)23.1 (4.5)
Total energy (kcal), mean (SD)a1221 (531)2127 (717)3095 c (1278)1248 (624)1933 (704)3138c (1257)2322 (1312)2091 (1401)1879 (856)2041 (956)1959 (983)224 (1668)
Cigarette smoking (% ever)b48.150.055.252.343.658.648.055.853.754.151.053.3
Age @ 1st intercourse (yr), mean (SD)a17 (3)17 (3)17 (2)17 (3)17 (3)16 (2)17 (2)17 (4)16 (2)17 (3)17 (4)16 (2)
Lifetime # sexual partners, mean (SD)a9 (8)10 (10)9 (7)10 (9)9 (8)10 (9)8 (9)11 (11)10 (7)11 (9)9 (11)9 (7)
Parity (% ever)b27.321.213.830.715.419.028.030.815.023.023.524.4
Oral contraceptive use (%)b
 Never14.310.619.016.96.422.422.011.57.59.513.717.8
 Current47.836.439.747.741.034.542.046.241.856.843.120.0
 Past39.053.041.435.352.643.136.042.350.833.843.162.2c
  • a Analysis of covariance.

  • b Pearson λ2 test of association.

  • c P < 0.05.