Disease-Specific Self-efficacy in Spasmodic Dysphonia

Abstract

Objective: Self-efficacy (SE) is an optimistic self-belief that one can cope with adversity. For chronic conditions, a standardized measure of SE is a strong predictor of health behaviors. Our objectives were to study SE in spasmodic dysphonia (SD) and to develop a disease-specific SE-SD scale.

Method: Disease-specific SE-SD items were developed through expert opinion. These items, general SE scale, Voice Handicap Index (VHI), Consensus Auditory Perceptual Evaluation of Voice (CAPE-V), and Hospital Anxiety and Depression Scale (HADS) were administered to SD patients who presented to University of Washington for botulinum toxin injections over a 6-month period.

Results: Eighty SD patients completed the study with a mean age 58.7 years. The general self-efficacy score (Cronbach’s α = .871) was 34.7 ± 3.7 out of 40 and was negatively correlated with VHI (r = −0.22, P = .08), CAPEV (r = −0.14, P = .36), and HADS-A (r = −0.50, P < .001) and HADS-D (r = −0.53, P < .001). Factor analysis was performed and selected 7 items from the general self-efficacy scale and 6 disease-specific SE-SD items to generate a 13-item disease specific SE-SD scale (Cronbach’s α = .913). Disease-specific SE-SD score was 43.9 ± 5.6 out of 52 and is negatively correlated with VHI (r = −0.35, P = .001), CAPE-V (r = −0.29, P = .026), HADS-A (r = −0.49, P < .001), and HADS-D (r = −0.58, P < .001).

Conclusion: SD patients who are established with botulinum toxin injections have a high degree of general SE and disease-specific SE. Patients with higher SE demonstrate higher subjective and objective vocal quality and lower levels of anxiety and depression. A 13-item disease specific SE-SD scale has been developed.