title: Elucidating the mechanisms linking early pubertal timing, sexual activity, and substance use for maltreated versus nonmaltreated adolescents.
abstract: OBJECTIVE
  To test models linking pubertal timing, peer substance use, sexual behavior, and substance use for maltreated versus comparison adolescents. Three theoretical mechanisms were tested: (1) peer influence links early pubertal timing to later sexual behavior and substance use; (2) early maturers engage in substance use on their own and then select substance-using friends; or (3) early maturers initiate sexual behaviors which lead them to substance-using peers.
  
  
  METHODS
  The data came from a longitudinal study of the effects of child maltreatment on adolescent development (303 maltreated and 151 comparison adolescents; age, 9-13 years at initial wave). Multiple-group structural equation models tested the hypotheses across three time points including variables of pubertal timing, perception of peer substance use, sexual behavior, and self-reported substance use.
  
  
  RESULTS
  Early pubertal timing was associated with substance-using peers only for maltreated adolescents, indicating the mediation path from early pubertal timing through substance-using peers to subsequent adolescent substance use and sexual behavior only holds for maltreated adolescents. Mediation via sexual behavior was significant for both maltreated and comparison adolescents. This indicates that sexual behavior may be a more universal mechanism linking early maturation with risky friends regardless of adverse life experiences.
  
  
  CONCLUSIONS
  The findings are a step toward elucidating the developmental pathways from early puberty to risk behavior and identifying early experiences that may alter mediation effects.
authors.affiliation: School of Social Work, University of Southern California, Los Angeles, California. Electronic address: negriff@usc.edu.
authors.forename: Sonya
authors.initials: S
authors.lastname: Negriff
authors.affiliation: Department of Family Medicine, David Geffen School of Medicine at UCLA, Los Angeles, California.
authors.forename: Matthew
authors.initials: M
authors.lastname: Brensilver
authors.affiliation: School of Social Work, University of Southern California, Los Angeles, California; Department of Psychology, University of Southern California, Los Angeles, California.
authors.forename: Penelope K
authors.initials: PK
authors.lastname: Trickett
mesh_terms: D000293:Adolescent; D041923:Adolescent Development / Q000502:physiology; D002648:Child; D002649:Child Abuse / Q000523:psychology*; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008385:Marijuana Smoking / Q000523:psychology*; D011627:Puberty / Q000502:physiology*; D012309:Risk-Taking; D012725:Sexual Behavior / Q000502:physiology*; D000066608:Underage Drinking / Q000523:psychology*
keywords: Maltreatment; Pubertal timing; Sexual activity; Substance use