Exploring physiotherapists’ personality traits that may influence treatment outcome in patients with chronic diseases: a cohort study

BACKGROUND: During treatment of patients with Chronic Diseases (CD) the therapist-patient interaction is often intense, and the strategies used during treatment require physiotherapists to assume a coaching role. Uncovering therapist factors that explain inter-therapist variation might provide tools to improve treatment outcome and to train future therapists. The purpose of this study was to explore the so-called 'therapist-effect', by looking at the influence of intrinsic therapist factors, specifically personality traits, on treatment outcome in patients with CD. METHODS: A cohort study was performed using data from the NIVEL Primary Care Database (NPCD) in 2011-2012 and an additional questionnaire. Patients with CD (n = 393) treated by Dutch physiotherapists working in outpatient practices (n = 39) were included. Patient and treatment outcome variables were extracted from NPCD. The course of complaint was measured using the Numeric Rating Scale. Therapist variables were measured using a questionnaire consisting of demographics and the Big Five traits: Extraversion, Neuroticism, Agreeableness, Conscientiousness and Openness to experiences. Data were analysed using multilevel linear regression. RESULTS: Only Neuroticism was found to be significant (Neuroticism F = 0.71, P = 0.01; therapist gender F = 0.72, P = 0.03; life events F = -0.54, P = 0.09; patient gender F = -0.43, P = 0.10; patient age F = 0.01, P = 0.27). Subgroup analyses of 180 patients with Osteoarthritis and 30 therapists showed similar results. CONCLUSIONS: There are indications that patients with CD who are treated by therapists who tend to be calmer, more relaxed, secure and resilient have a greater reduction in severity of complaints compared to patients treated by therapists who show less of these traits. Being a male therapist and having experienced life events influence outcome positively. However, more extensive research is needed to validate the current findings.