Reliability and Validity of an Observational Measure of Client Decision-Making: The Client Language Assessment -...

The Client Language Assessment - Proximal/Distal (CLA-PD) is a language rating system for measuring client decision-making in interventions that target a specified behavior change (e.g., alcohol or other drug use). In the CLA-PD, there are five dimensions of change language (Reason, Ability, Commitment, Taking Steps, Other) adapted from the client portion of the Motivational Interviewing Skill Code (MISC). For the CLA-PD, language codes are sub-divided to discriminate statements regarding the primary, or target behavior change (distal change) from the intermediate coping activities (proximal change) that are prescribed to facilitate that target behavior change. The goal of the CLA-PD is to allow for higher specificity than existing client language measures, when process studies consider interventions that are multi-session and skill-based (e.g., cognitive behavioral therapy).

Three raters received 40 hours of training on the use of the CLA-PD. The data were a sample of therapy session audio-files from a completed clinical trial (N=126), which enabled examination of client language across four sessions (i.e., first three and final attended) of three evidence-based alcohol interventions (cognitive behavioral therapy, twelve-step facilitation therapy, motivational enhancement therapy).

Inter-rater reliability results for summary scores showed "excellent" reliability for the measure. Specifically, two-way mixed intraclass coefficients ranged from .83 to .95. Internal consistency reliability showed alphas across sessions that ranged from "fair" to "good" (α=.74-.84). In convergent and discriminant validity analyses using data independently measured with MISC-based ratings, the pattern of results was as would be expected. Specifically, convergent correlations, by valence (i.e., change and sustain talk), between CLA-PD Distal and MISC-based language scores were moderate (r=.46-.55, p<.001) while discriminant correlations by valence for CLA-PD Proximal and MISC-based language scores were small (r=.22-.24, p<.05). Finally, proportion Change Talk Proximal predicted subsequent session coping behaviors (i.e., processes of change) as well as 3-month Alcoholics Anonymous involvement and attendance (ps<.05-.005), but not 3-month alcohol abstinence self-efficacy. Further, analyses of criterion predictive validity showed that proportion Change Talk Distal predicted 3- and 12-month drinking frequency and quantity measures (ps<.05-.005).

When behavior change treatments are multi-session and/or skill-based, the present analyses suggest the CLA-PD is a promising, psychometrically sound observational rating measure of client verbalized decision-making.