title: Pubertal assessment method and baseline characteristics in a mixed longitudinal study of girls.
abstract: OBJECTIVE
  The objective of this study was to describe the assessment methods and maturation status for a multisite cohort of girls at baseline recruitment and at ages 7 and 8 years.
  
  
  METHODS
  The method for pubertal maturation staging was developed collaboratively across 3 sites. Girls at ages 6 to 8 years were recruited at 3 sites: East Harlem, New York; greater Cincinnati metropolitan area; and San Francisco Bay area, California. Baseline characteristics were obtained through interviews with caregivers and anthropometric measurements by trained examiners; breast stage 2 was defined as onset of pubertal maturation. The kappa statistic was used to evaluate agreement between master trainers and examiners. Logistic regression models were used to identify factors that are associated with pubertal maturation and linear regression models to examine factors that are associated with height velocity.
  
  
  RESULTS
  The baseline cohort included 1239 girls. The proportion of girls who had attained breast stage 2 varied by age, race/ethnicity, BMI percentile, and site. At 7 years, 10.4% of white, 23.4% of black non-Hispanic, and 14.9% of Hispanic girls had attained breast stage>or=2; at 8 years, 18.3%, 42.9%, and 30.9%, respectively, had attained breast stage>or=2. The prime determinant of height velocity was pubertal status.
  
  
  CONCLUSIONS
  In this multisite study, there was substantial agreement regarding pubertal staging between examiners across sites. The proportion of girls who had breast development at ages 7 and 8 years, particularly among white girls, is greater than that reported from studies of girls who were born 10 to 30 years earlier.
authors.affiliation: Cincinnati Children's Hospital Medical Center, Adolescent Medicine (ML 4000), and Department of Environmental Health, University of Cincinnati College of Medicine, 3333 Burnet Ave, Cincinnati, OH 45229-3039, USA. frank.biro@cchmc.org
authors.forename: Frank M
authors.initials: FM
authors.lastname: Biro
authors.forename: Maida P
authors.initials: MP
authors.lastname: Galvez
authors.forename: Louise C
authors.initials: LC
authors.lastname: Greenspan
authors.forename: Paul A
authors.initials: PA
authors.lastname: Succop
authors.forename: Nita
authors.initials: N
authors.lastname: Vangeepuram
authors.forename: Susan M
authors.initials: SM
authors.lastname: Pinney
authors.forename: Susan
authors.initials: S
authors.lastname: Teitelbaum
authors.forename: Gayle C
authors.initials: GC
authors.lastname: Windham
authors.forename: Lawrence H
authors.initials: LH
authors.lastname: Kushi
authors.forename: Mary S
authors.initials: MS
authors.lastname: Wolff
mesh_terms: D002648:Child; D003955:Diagnostic Tests, Routine; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D011627:Puberty / Q000502:physiology