TABLE 1

Participants’ Characteristics (N = 3474)

Characteristics
Maternal
 Age at enrollment, y30.9 (5.0)
  Missing data0
 Education, n (%)
  Primary630 (18.1)
  Secondary945 (27.2)
  High1674 (48.2)
  Missing data225 (6.5)
 Antenatal psychiatric symptoms0.15 (0.06 to 0.31)
  Missing data
 Smoking during pregnancy, n (%)672 (20.8)
  Missing data250 (7.2)
 Household income, n (%)
  Poor168 (4.8)
  Low389 (11.2)
  Modal and above2098 (60.4)
  Missing data819 (23.6)
Partner
 Age at enrollment, y33.5 (5.4)
  Missing data977
 Education %
  Primary395 (11.4)
  Secondary594 (17.1)
  High1239 (35.7)
  Missing data1246 (35.9)
Child
 Age at neuromotor assessment, wk12.6 (2.0)
  Missing data0
 Sex, boy (%)1702 (49.0)
  Missing data0
 Ethnic background, n (%)
  Dutch1858 (53.5)
  Other Western388 (11.2)
  Non-Western1167 (33.6)
  Missing data61 (1.8)
 Gestational age at birth, wk39.9 (1.7)
  Missing data5
 Instrument (9–15 wk), %2802 (80.7)
 Instrument (15–20 wk), %672 (19.3)
  Missing data0
  • Numbers are mean (SD) for variables with normal distribution, median (quartile range) for not-normally distributed variables, and percentages for categorical variables.