Multilevel Exploratory Factor Analysis of the Feeling Word Checklist-24.

Emotional reactions are a vital part of the therapeutic relationship. The Feeling Word Checklist-24 (FWC-24) is an instrument asking the clinician (or the patient) to report to what degree he or she has experienced various feelings during a therapeutic interaction. The aim of this study was to assess the factor structure of the clinician-rated FWC-24 when taking dependencies in the data into account. The sample was deliberately heterogeneous and consisted of 4,443 ratings made by 101 psychotherapists working with different psychotherapy methods in relation to 191 patients of different ages, genders, and with different primary diagnoses. A random intercept-only model revealed large intraclass correlation coefficients at the therapist level, indicating that a multilevel analysis was warranted. A two-level exploratory factor analysis with therapists as the between level and patients plus sessions as the within level was conducted. The items from FWC-24 were found to be best represented by four factors on the between level and four factors on the within level. The factor structures were largely similar on the two levels and were labeled Engaged, Inadequate, Relaxed, and Moved. The different factors explained different amounts of variance on different levels, indicating that some factors are more therapist dependent and some more patient dependent.