title: Validation of the Abdominal Pain Index using a revised scoring method.
abstract: OBJECTIVE
  Evaluate the psychometric properties of child- and parent-report versions of the four-item Abdominal Pain Index (API) in children with functional abdominal pain (FAP) and healthy controls, using a revised scoring method that facilitates comparisons of scores across samples and time.
  
  
  METHODS
  Pediatric patients aged 8-18 years with FAP and controls completed the API at baseline (N = 1,967); a subset of their parents (N = 290) completed the API regarding the child's pain. Subsets of patients completed follow-up assessments at 2 weeks (N = 231), 3 months (N = 330), and 6 months (N = 107). Subsets of both patients (N = 389) and healthy controls (N = 172) completed a long-term follow-up assessment (mean age at follow-up = 20.21 years, SD = 3.75).
  
  
  RESULTS
  The API demonstrated good concurrent, discriminant, and construct validity, as well as good internal consistency.
  
  
  CONCLUSIONS
  We conclude that the API, using the revised scoring method, is a useful, reliable, and valid measure of abdominal pain severity.
authors.affiliation: Department of Psychology and Human Development, Vanderbilt University and Department of Pediatrics, Vanderbilt University lynn.walker@vanderbilt.edu.
authors.forename: Kelsey T
authors.initials: KT
authors.lastname: Laird
authors.affiliation: Department of Psychology and Human Development, Vanderbilt University and Department of Pediatrics, Vanderbilt University.
authors.forename: Amanda L
authors.initials: AL
authors.lastname: Sherman
authors.affiliation: Department of Psychology and Human Development, Vanderbilt University and Department of Pediatrics, Vanderbilt University.
authors.forename: Craig A
authors.initials: CA
authors.lastname: Smith
authors.affiliation: Department of Psychology and Human Development, Vanderbilt University and Department of Pediatrics, Vanderbilt University.
authors.forename: Lynn S
authors.initials: LS
authors.lastname: Walker
mesh_terms: D015746:Abdominal Pain / Q000175:diagnosis*; D000293:Adolescent; D002648:Child; D005260:Female; D006801:Humans; D008297:Male; D010290:Parents; D010372:Pediatrics; D010808:Physical Examination; D011594:Psychometrics
keywords: abdominal pain; chronic pain; pain severity; parent report; pediatric pain