Longitudinal measurement invariance of the Working Alliance Inventory - Short form across coaching sessions

Activity: Talk or presentation typesConference contribution (without a publication)Academic


The Working Alliance Inventory Short form (WAI-S) for coaching charts the quality of working alliance through coaching sessions and is broadly applied in coaching research.
Due to a shortfall in such research on psychometric properties of the WAI-S, the purpose of this study was to examine (a) if the theorized three-factor structure of the 12-item WAI-S forms a solid representation of the dimensions of working alliance in coaching, and (b) longitudinal measurement invariance (LMI) of the WAI-S.
Data were collected in a two-wave study design among N = 690 Dutch coachees that completed the questionnaire at the first measurement, of which N = 490 also completed the questionnaire at the second measurement.
Confirmatory factor analyses evidenced best fit of the three-factor model in comparison to one-, and two-factor models at both time points. Despite the fact that multigroup confirmatory factor analysis detected non-invariant intercepts, our findings overall supported measurement invariance across coaching sessions.
As decisions in both clinical and scientific practices generally rely on outcome assessment of interpersonal change in scores on the same measure over time, we believe our findings to be of contributing value to the consolidation of interpretation and accuracy of scorings on the WAI-S in coaching.
Period8 Sept 2022
Event titleEMCC Global Research Conference: Celebrating and flourishing: A Dialogue Between Research & Practice in Coaching, Mentoring and Supervision
Event typeConference
LocationBrussels, BelgiumShow on map
Degree of RecognitionInternational


  • coaching
  • working alliance inventory
  • WAI-S
  • Longitudinal measurement invariance
  • psychometrics