title: Item response theory analysis of Working Alliance Inventory, revised response format, and new Brief Alliance Inventory.
abstract: The Working Alliance Inventory (WAI) has made great contributions to psychotherapy research. However, studies suggest the 7-point response format and 3-factor structure of the client version may have psychometric problems. This study used Rasch item response theory (IRT) to (a) improve WAI response format, (b) compare two brief 12-item versions (WAI-sr; WAI-s), and (c) develop a new 16-item Brief Alliance Inventory (BAI).
  
  
  
  Archival data from 1786 counseling center and community clients were analyzed.
  
  
  
  IRT findings suggested problems with crossed category thresholds. A rescoring scheme that combines neighboring responses to create 5- and 4-point scales sharply reduced these problems. Although subscale variance was reduced by 11-26%, rescoring yielded improved reliability and generally higher correlations with therapy process (session depth and smoothness) and outcome measures (residual gain symptom improvement). The 16-item BAI was designed to maximize "bandwidth" of item difficulty and preserve a broader range of WAI sensitivity than WAI-s or WAI-sr.
  
  
  
  Comparisons suggest the BAI performed better in several respects than the WAI-s or WAI-sr and equivalent to the full WAI on several performance indicators.
authors.affiliation: a Department of Psychology , University of Tennessee , Knoxville , TN , USA.
authors.forename: Brent
authors.initials: B
authors.lastname: Mallinckrodt
authors.affiliation: a Department of Psychology , University of Tennessee , Knoxville , TN , USA.
authors.forename: Yacob T
authors.initials: YT
authors.lastname: Tekie
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D008297:Male; D017063:Outcome Assessment, Health Care / Q000592:standards*; D011369:Professional-Patient Relations; D011594:Psychometrics / Q000295:instrumentation*; D011613:Psychotherapy / Q000592:standards*
keywords: instrument development; item response theory; psychotherapy outcome; psychotherapy process; psychotherapy working alliance