An introduction to item response theory for health behavior researchers. Academic Article uri icon


  • OBJECTIVE: To introduce item response theory (IRT) to health behavior researchers by contrasting it with classical test theory and providing an example of IRT in health behavior. METHOD: Demonstrate IRT by fitting the 2PL model to substance-use survey data from the Adolescent Health Risk Behavior questionnaire (n=1343 adolescents). RESULTS: An IRT 2PL model can produce viable substance use scores that differentiate different levels of substance use, resulting in improved precision and specificity at the respondent level. CONCLUSION: IRT is a viable option for health researchers who want to produce high-quality scores for unidimensional constructs. The results from our example-although not flawless-demonstrate the feasibility of IRT in health behavior research.

published proceedings

  • Am J Health Behav

altmetric score

  • 1.5

author list (cited authors)

  • Warne, R. T., McKyer, E., & Smith, M. L.

citation count

  • 14

complete list of authors

  • Warne, Russell T||McKyer, EJ Lisako||Smith, Matthew L

publication date

  • January 2012