title: Test-Retest Reliability of a Computerized Adaptive Depression Screener.
abstract: Computerized adaptive testing (CAT) provides improved precision and decreased test burden compared with traditional, fixed-length tests. Concerns have been raised regarding reliability of CAT-based measurements because the items administered vary both between and within individuals over time. The study measured test-retest reliability of the CAT Depression Inventory (CAT-DI) for assessment of depression in a screening setting where most scores fall in the normal range.
  
  
  
  A random sample of adults (N=101) at an academic emergency department (ED) was screened twice with the CAT-DI during their visit. Test-retest scores, bias, and reliability were assessed.
  
  
  
  Fourteen percent of patients scored in the mild range for depression, 4% in the moderate range, and 3% in the severe range. Test-retest scores were without significant bias and had excellent reliability (r=.92).
  
  
  
  The CAT-DI provided reliable screening results among ED patients. Concerns about whether changes in item presentation during repeat testing would affect test-retest reliability were not supported.
authors.affiliation: Dr. Beiser and Ms. Vu are with the Section of Emergency Medicine, and Dr. Gibbons is with the Center for Health Statistics, University of Chicago, Chicago. Send correspondence to Dr. Gibbons (e-mail: rdg@uchicago.edu ).
authors.forename: David
authors.initials: D
authors.lastname: Beiser
authors.affiliation: Dr. Beiser and Ms. Vu are with the Section of Emergency Medicine, and Dr. Gibbons is with the Center for Health Statistics, University of Chicago, Chicago. Send correspondence to Dr. Gibbons (e-mail: rdg@uchicago.edu ).
authors.forename: Milkie
authors.initials: M
authors.lastname: Vu
authors.affiliation: Dr. Beiser and Ms. Vu are with the Section of Emergency Medicine, and Dr. Gibbons is with the Center for Health Statistics, University of Chicago, Chicago. Send correspondence to Dr. Gibbons (e-mail: rdg@uchicago.edu ).
authors.forename: Robert
authors.initials: R
authors.lastname: Gibbons
mesh_terms: D000293:Adolescent; D000328:Adult; D003863:Depression / Q000175:diagnosis*; D003866:Depressive Disorder / Q000175:diagnosis*; D003936:Diagnosis, Computer-Assisted / Q000592:standards*; D004636:Emergency Service, Hospital; D006801:Humans; D008875:Middle Aged; D015203:Reproducibility of Results; D055815:Young Adult