An investigation of reliability of the Sunderland Tracheosophageal Voice Perceptual Scale

Abstract

Background: The Sunderland Tracheosophageal Voice Perceptual scale (SToPS) is the only perceptual rating scale designed specifically for tracheosophageal voice [Hurren et al.: Clin Otolaryngol. 2009 Dec; 34(6): 533–8]. Objective: To investigate the inter rater reliability of the SToPS when analyzing alaryngeal voice. Methods: Prospective evaluation of inter rater reliability of the SToPS based on audio recordings of 230 voice samples from 41 laryngectomy patients rated by 3 experts. Interval data were analyzed using intraclass correlation coefficients (ICC) while categorical data were analyzed using Kappa. Results: ICC of above 0.6 was observed between raters for each prosthesis on a majority of parameters demonstrating a good level of reliability. Reliability was fair (ICC of between 0.40 and 0.59) on Q11 (Articulatory precision) and Q12 (Paralinguistics). Reliability was also fair (0.21–0.40) or slight (0.00–0.20) for Q2 (Tonicity), which was analyzed using Kappa. Kappa above 0.61 signified a good level of reliability. Conclusions: This study demonstrates good rater reliability for the majority of parameters on the SToPS scale, supporting the use of this tool within the clinical realm. However, further research is required to ascertain if any methods of increasing inter rater reliability on those parameters which did not reach good reliability can be identified.