TABLE 1

Weighted Demographic Characteristics of Study Population (N = 3297)

DemographicNaWeighted (%)US Vital Statistics (2011–2013)
Maternal age (y)
 <202757.57.8
 20–29178852.251.6
 ≥30123440.340.6
Maternal education
 <HS47812.817.1
 HS or GED83323.525.1
 Some college104130.829.0
 ≥College degree93232.928.8
Parity
 1121537.939.7
 2109533.731.5
 ≥397828.428.3
Maternal race and/or ethnicity
 Non-Hispanic white127552.354.1
 Non-Hispanic African American82812.914.8
 Hispanic91226.023.0
 Other2818.88.0
Income ($)
 <20 000115829.5NA
 20 000–49 99983824.8NA
 ≥50 00057719.8NA
 Unknown72426.0NA
Region
 Northeast63421.2NA
 Midwest49612.8NA
 South138341.5NA
 West78424.5NA
Infant age (wk)
 8–11202662.9NAb
 12–1556417.0NAb
 16–193239.4NAb
 ≥2038410.7NAb
Infant sex
 Girl168550.748.8
 Boy160849.351.2
Infant birth weight (g)
 <2500 2025.78.0
 ≥2500 307694.391.9
  • GED, general education development; HS, high school; NA, not available/applicable.

  • a Not all numbers add up to 3297 because of missing data.

  • b US Vital Statistics Data not applicable to infant age at time of survey response.