Brief scales for the measurement of target variables and processes of change in cognitive behaviour therapy for major depression, panic disorder and social anxiety disorder.

Abstract

The measurement of process variables derived from cognitive behavioural theory can aid treatment development and support the clinician in following treatment progress. Self-report process measures are ideally brief, which reduces the burden on patients and facilitates the implementation of repeated measurements. To develop 13 brief versions (3-6 items) of existing cognitive behavioural process scales for three common mental disorders: major depression, panic disorder, and social anxiety disorder. Using data from a real-world teaching clinic offering internet-delivered cognitive behavior therapy (n=370), we drafted brief process scales and then validated these scales in later cohorts (n=293). In the validation data, change in the brief process scales significantly mediated change in the corresponding domain outcomes, with standardized coefficient point estimates in the range of -0.53 to -0.21. Correlations with the original process scales were substantial (r=.83-.96), internal consistency was mostly adequate (α=0.65-0.86), and change scores were moderate to large (|d|=0.51-1.18). For depression, the brief Behavioral Activation for Depression Scale-Activation subscale was especially promising. For panic disorder, the brief Agoraphobic Cognitions Questionnaire-Physical Consequences subscale was especially promising. For social anxiety disorder, the Social Cognitions Questionnaire, the Social Probability and Cost Questionnaire, and the Social Behavior Questionnaire-Avoidance and Impression Management subscales were all promising. Several brief process scales showed promise as measures of treatment processes in cognitive behaviour therapy. There is a need for replication and further evaluation using experimental designs, in other clinical settings, and preferably in larger samples.