Quantitative methods for the analysis of verbal interactions in psychotherapy

When psychotherapy is viewed as an interpersonal and interactive process, sequential methods for analyzing the intersubjective dimension of the psychotherapeutic dialogue become a strategic tool. In the first section, this chapter shows a short overview of the currently used methods in the quantitative approach to verbal interactions, and particularly those statistical tools able to handle information collected as a sequence of countable events. Then in the second section, we propose a process to move from recorded interviews to a statistically summarized result (see Fig. 10.1). The sequential steps identified in this process aim to codify the interviews, transferring them into a stream of units, classified by a nominal scale. Since every unit can be univocally assigned to a specific category, observations become countable. Despite the limitations of a nominal scale, this information may be quantitatively summarized by using appropriate statistical techniques based on frequency counts.