Treatment Outcome Measures for Spasmodic Dysphonia: A Systematic Review

Abstract

Purpose: This systematic review aims to identify instruments used to evaluate treatment outcomes for people with spasmodic dysphonia.

Methods: Electronic database (PubMed, Cochrane Library, Embase, and CINAHL) searches and hand-searching identified studies that evaluated treatment approaches for spasmodic dysphonia which included pre and post outcome data.

Results: A total of 4714 articles were retrieved from searching databases; 1165 were duplicates. Titles and abstracts of 3549 were screened, with 171 being selected for full-text review. During full-text review, 101 articles were deemed suitable for inclusion. An additional 24 articles were identified as suitable for inclusion through hand-searching of reference lists. Data was extracted from 125 studies, identifying 220 outcome measures. As per the World Health Organization's International Classification of Functioning (ICF), the majority measured body functions (n = 212, 96%). Outcomes that explored communication and participation in everyday life and attitudes towards communication (ie, activity and participation domains) were infrequent (n = 8; 4%). Quality of life, a paradigm outside of the scope of the ICF, was also captured by four outcome measures. No instruments evaluating communication partners' perspectives were identified.

Conclusions: Currently there is no unified approach to the measurement of outcomes in SD treatment research. Development and implementation of a core outcome set is recommended to facilitate improved understanding of the efficacy of current and new treatment options.

Keywords: Laryngeal dystonia; Outcome measures; Spasmodic dysphonia; Systematic review; Treatment outcomes.