Descriptive analysis of the verbal behavior of a therapist: a known-group validity analysis of the putative behavioral functions involved in clinical interaction.

This study analyzes the interobserver agreement and hypothesis-based known-group validity of the Therapist's Verbal Behavior Category System (SISC-INTER). The SISC-INTER is a behavioral observation protocol comprised of a set of verbal categories representing putative behavioral functions of the in-session verbal behavior of a therapist (e.g., discriminative, reinforcing, punishing, and motivational operations). The complete therapeutic process of a clinical case of an individual with marital problems was recorded (10 sessions, 8 hours), and data were arranged in a temporal sequence using 10-min periods. Hypotheses based on the expected performance of the putative behavioral functions portrayed by the SISC-INTER codes across prevalent clinical activities (i.e., assessing, explaining, Socratic method, providing clinical guidance) were tested using autoregressive integrated moving average (ARIMA) models. Known-group validity analyses provided support to all hypotheses. The SISC-INTER may be a useful tool to describe therapist-client interaction in operant terms. The utility of reliable and valid protocols for the descriptive analysis of clinical practice in terms of verbal behavior is discussed.