title: Skeletal maturity and socio-economic status in Portuguese children and youths: the Madeira growth study.
abstract: BACKGROUND
  Skeletal maturity is used to evaluate biological maturity status. Information about the association between socio-economic status (SES) and skeletal maturity is limited in Portugal.
  
  
  OBJECTIVE
  The aim of this study is to document the skeletal maturity of youths in Madeira and to evaluate variation in maturity associated with SES.
  
  
  METHODS
  The study involved 507 subjects (256 boys and 251 girls) from the Madeira Growth Study, a mixed-longitudinal study of five cohorts (8, 10, 12, 14 and 16 years of age) followed at yearly intervals over 3 years (1996-1998). A total of 1493 observations were made. Skeletal age was estimated from radiographs of the hand and wrist using the Tanner-Whitehouse 2 method (TW2). Social class rankings were based on method. Five social rankings were subsequently grouped into three SES categories: high, average and low.
  
  
  RESULTS
  Median for the radius, ulna and short finger bones (RUS scores) in the total sample of boys and girls increased curvilinearly across age whereas median for the 7 (without pisiform) carpal bones (Carpal scores) increased almost linearly. The 20-bone maturity scores demonstrated distinctive trends by gender: the medians for boys increased almost linearly while the medians for girls increased curvilinearly. SES differences were minimal. Only among children aged 10-11 years were high SES boys and girls advanced in skeletal maturity. Madeira adolescents were advanced in skeletal maturity compared with Belgian reference values.
  
  
  CONCLUSIONS
  The data suggests population variation in TW2 estimates of skeletal maturation. Skeletal maturity was not related to SES in youths from Madeira.
authors.affiliation: Department of Physical Education and Sports, University of Madeira, Autonomous Region of Madeira, Portugal. dfreitas@uma.pt
authors.forename: D
authors.initials: D
authors.lastname: Freitas
authors.forename: J
authors.initials: J
authors.lastname: Maia
authors.forename: G
authors.initials: G
authors.lastname: Beunen
authors.forename: J
authors.initials: J
authors.lastname: Lefevre
authors.forename: A
authors.initials: A
authors.lastname: Claessens
authors.forename: A
authors.initials: A
authors.lastname: Marques
authors.forename: A
authors.initials: A
authors.lastname: Rodrigues
authors.forename: C
authors.initials: C
authors.lastname: Silva
authors.forename: M
authors.initials: M
authors.lastname: Crespo
authors.forename: M
authors.initials: M
authors.lastname: Thomis
authors.forename: A
authors.initials: A
authors.lastname: Sousa
authors.forename: R
authors.initials: R
authors.lastname: Malina
mesh_terms: D000293:Adolescent; D000365:Age Determination by Skeleton; D001846:Bone Development / Q000502:physiology*; D001133:Bones of Upper Extremity / Q000000981:diagnostic imaging*; D002648:Child; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D011174:Portugal; D012016:Reference Values; D012727:Sex Characteristics; D012959:Socioeconomic Factors