Within and between associations of clinical microskills and correct application of techniques/strategies: A longitudinal multilevel approach.

Objective: The therapist effect has been demonstrated in various studies. However, studies on putative therapist characteristics show heterogeneous results. Although the majority of studies have solely examined effects between therapists, a growing interest in effects within therapists has emerged. However, it remains unclear whether therapist characteristics are rather a state-like than a trait-like phenomenon. The main aim of the present study is to test whether clinical microskills as well as correct application of techniques and strategies (both between and within therapists) predict across-session change of symptom severity in a large naturalistic data set.

Method: The results are based on 398 patients and 48 therapists who treated 5-17 patients each. Clinical microskills and correct application of techniques/strategies were rated using the Inventory of Therapeutic Interventions and Skills, and symptom severity was assessed with the Hopkins Symptom Checklist-11.

Results: Results demonstrated significant within- and between-therapist variability in clinical microskills and correct application of techniques/strategies, and no change over the course of treatment in both variables. Moreover, correct application of techniques/strategies was significantly associated with symptom improvement within, but not between therapists. In addition, higher treatment difficulty as well as an interaction between treatment difficulty and correct application of techniques/strategies were significantly associated with symptom improvement. Clinical microskills were neither predictive of symptom improvement within nor between therapists.

Conclusions: These results provide initial evidence that not the therapist's average correct application of techniques/strategies is important, but rather how correctly they use a technique with a specific patient. (PsycInfo Database Record (c) 2022 APA, all rights reserved).