title: Utility of percentage of births to teenagers as a surrogate for the teen birth rate.
abstract: OBJECTIVE
  The teen birth rate is commonly used in comparing regional variation in teen pregnancies, but local teen birth rates are not always available. In this study the percentage of all births that are to teens was evaluated for its utility as a surrogate for the teen birth rate.
  
  
  METHODS
  Rank correlation and sensitivity and specificity analyses were used.
  
  
  RESULTS
  The Spearman rank correlations between percentage of teen births (PTB) and teen birth rate (TBR) were .995, .906, and .841 for the 3 age groups suggesting that it may be reasonable to employ PTB to prioritize zip codes. Zip codes with upper quartile levels of percentages of teen births identified zip codes with upper quartile levels of TBR with a sensitivity of 83.8%, 68.8%, and 65%; a false-positive rate of 2.1%, 8.6%, and 10%; and a positive predictive value of 89.3%, 67.6%, and 67.5% for the age groups 10 through 14, 15 through 17, and 18 through 19 years.
  
  
  CONCLUSIONS
  The percentage of births to teens is a useful surrogate for teen birth rate in California, especially among younger teenagers.
authors.affiliation: Maternal and Child Health Program, School of Public Health, University of California, Berkeley 94720-7360, USA. jgould@uclink4.berkeley.edu
authors.forename: J
authors.initials: J
authors.lastname: Gould
authors.forename: T
authors.initials: T
authors.lastname: Blackwell
authors.forename: C
authors.initials: C
authors.lastname: Heilig
authors.forename: M
authors.initials: M
authors.lastname: Axley
mesh_terms: D000293:Adolescent; D001723:Birth Rate; D002140:California / Q000453:epidemiology; D003625:Data Collection / Q000706:statistics & numerical data; D003628:Database Management Systems / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D011247:Pregnancy; D011256:Pregnancy Outcome; D011253:Pregnancy in Adolescence / Q000706:statistics & numerical data*; D012680:Sensitivity and Specificity