The assessment of cognitive-behavioral therapy skills in patients diagnosed with health anxiety: Development and pilot study on an observer-based rating scale.

Cognitive-behavioral therapy is a highly effective treatment of health anxiety, but it remains unclear through which mechanisms treatment effects prevail. Some evidence suggests that patients acquire skills-understood as techniques helping them reach therapy goals-through psychotherapy. In the current study, an observer-based rating scale for the skills assessment of patients with health anxiety (SAPH) was developed and validated in a pilot study. Based on 177 videotapes, four independent raters evaluated the frequency of skills acquired during cognitive and exposure therapy among 66 patients diagnosed with health anxiety with the SAPH. Predictive validity was evaluated by the Yale-Brown Obsessive-Compulsive Scale for Hypochondriasis. The SAPH demonstrated good interrater reliability (ICC(1,2)  = .88, p < .001, 95% CI [.81, .92]) and internal consistency (α = .94). Although patient skills did not significantly increase during three sessions, they significantly predicted a reduction in health anxiety symptoms at the end of treatment (R2  = .35). Patients' skills are highly important within the treatment of health anxiety. By providing external ratings of patients' skills with good psychometric properties, our pilot data suggest that the SAPH may complement current tools for the assessment of skills, specifically in targeting health anxiety.