title: Evaluating Coincident Relationships Between Obesity Incidence and Normal Weight Incidence From Birth Through Kindergarten for US Children.
abstract: OBJECTIVE
  We examine the concurrent relationship between obesity incidence and normal weight status incidence and prevalence in children between 9 months and kindergarten.
  
  
  METHODS
  Multistage, probability sample from the Early Childhood Longitudinal Study-Birth cohort.
  
  
  METHODS
  United States.
  
  
  METHODS
  Representative sample of US preschool children (n = 9950) followed from birth through kindergarten.
  
  
  METHODS
  From direct, anthropometric measures, we reported prevalence and incidence rates across 4 follow-up periods.
  
  
  METHODS
  In addition to prevalence and incidence rates, we reported risk ratios based on multiple definitions and estimated predicted probabilities of obesity and normal weight status using clinically meaningful body mass index (BMI)-for-age percentiles.
  
  
  RESULTS
  Obesity prevalence (13%-20%) was much smaller than normal weight status prevalence (66%-70%). Lower socioeconomic status, Hispanic, and non-Hispanic black children had greater risk of obesity. During 9 months to kindergarten, obesity incidence decreased two-thirds (15.6%), while normal weight status incidence decreased almost one-half (44.6%). Coincidently, normal weight status incidence (ranged from 23% to 45%) was consistently and substantially higher than obesity incidence (ranged from 5% to 15%). During 4 years to kindergarten, the obesity risk for overweight children was 13 times higher than that for normal weight status children.
  
  
  CONCLUSIONS
  Overall rates of obese and normal weight incidence were substantial at 9 months, trended lower, but remained high through kindergarten. At 4 years to kindergarten, children with relatively high initial BMI were very likely to become obese but far less likely to achieve normal weight status.
authors.affiliation: 1 Institute for Social Research, University of Michigan, Ann Arbor, MI, USA.
authors.forename: William H
authors.initials: WH
authors.lastname: Yeaton
authors.affiliation: 2 Department of Family and Preventive Medicine, Emory University, Atlanta, GA, USA.
authors.forename: Megha K
authors.initials: MK
authors.lastname: Shah
authors.affiliation: 3 School of Social Work, Wayne State University, Detroit, MI, USA.
authors.forename: Brian G
authors.initials: BG
authors.lastname: Moss
mesh_terms: D015992:Body Mass Index; D001835:Body Weight; D002675:Child, Preschool; D015331:Cohort Studies; D005260:Female; D006801:Humans; D015994:Incidence; D008137:Longitudinal Studies; D008297:Male; D009765:Obesity / Q000453:epidemiology*; D016017:Odds Ratio; D015995:Prevalence; D012307:Risk Factors; D012923:Social Class; D014481:United States
keywords: incidence; normal body weight; obese body weight; prevalence; young children weight status