TABLE 2

Characteristics of the Study Population, Comparing Those With and Without Infant BMI Data

With BMI Data (N = 2553)Without BMI Data (N = 317)
N or nMean ± SD, Median (IQR), or (%)N or nMean ± SD, Median (IQR), or (%)
Mother, N, mean ± SD
 Age, y255332.4 ± 4.631731.4 ± 5.2
 Diet quality (HEI score)238073.0 ± 8.524872.6 ± 8.7
 Prepregnancy BMI247624.7 ± 5.410325.3 ± 6.5
Infant, N, mean ± SD
 Gestational age, wk255339.9 ± 1.031739.8 ± 1.0
 Birth wt, g25323509 ± 4433173482 ± 465
 WFA at birth, z score25320.41 ± 0.893100.36 ± 0.95
 WFA at 12 mo, z score25530.30 ± 0.98
 Wt gain velocity, birth to 12 mo, change in WFA z score2532−0.11 ± 1.05
 BMI at 12 mo, z score25530.21 ± 1.07
Feeding, N, median (IQR)
 Duration of exclusive BF, mo24934.0 (0.5–5.0)1972.3 (0.3–5.0)
 Duration of any BF, mo232011.0 (6.0–15.0)1416.0 (2.0–11.0)
 Introduction to solid foods, mo24475.0 (4.5–6.0)1435.0 (3.5–5.0)
Study site, n (%)
 Edmonton560(21.9)110(34.7)
 Toronto597(23.4)95(30.0)
 Vancouver577(22.6)51(16.1)
 Winnipeg819(32.1)61(19.2)
Maternal ethnicity, n (%)
 Asian369(14.6)45(15.3)
 White1901(75.1)192(65.3)
 First Nations94(3.7)23(7.8)
 Other167(6.6)34(11.6)
 Missing2223
Maternal education, n (%)
 High school or less205(8.3)37(13.2)
 Some postsecondary368(14.9)41(14.6)
 Postsecondary1412(57.0)150(53.6)
 Postgraduate491(19.8)52(18.6)
 Missing7737
Maternal marital status, n (%)
 Married or common-law2368(94.7)256(90.1)
 Single (never married)118(4.7)23(8.1)
 Divorced or separated15(0.6)5(1.8)
 Missing5233
Maternal smoking, n (%)
 No2305(92.1)247(86.7)
 Yes198(7.9)38(13.3)
 Missing5032
Parity, n (%)
 01386(54.3)165(52.1)
 1844(33.1)117(36.9)
 2+322(12.6)35(11.0)
 Missing10
Infant sex, n (%)
 Female1224(47.9)154(48.6)
 Male1329(52.1)163(51.4)
  • Percentages reflect proportions of nonmissing data. Comparisons by t test, Mann–Whitney test, or χ2 test. N = 2870 infants from the CHILD cohort born ≥38 + 0 wk gestation. BF, breastfeeding; HEI, healthy eating index. —, not applicable.