Evaluation of Vocal Fold Motion Abnormalities: Are We All Seeing the Same Thing?

OBJECTIVES: Flexible laryngoscopy is the principle tool for the evaluation of vocal fold motion. As of yet, no consistent, unified outcome metric has been developed for vocal fold paralysis/immobility research. The goal of this study was to evaluate vocal fold motion assessment (inter- and intra-rater reliability) among general otolaryngologists and fellowship-trained laryngologists.

STUDY DESIGN: Prospective video perceptual analysis study.

METHODS: Flexible laryngoscopic examinations, with sound, of 15 unique patient cases (20 seconds each) were sent to 10 general otolaryngologists and 10 fellowship-trained laryngologists blinded to clinical history. Reviewers were given written definitions of vocal fold mobility and immobility and two video examples. The cases included bilateral vocal fold mobility (six), unilateral vocal fold immobility (five), and unilateral vocal fold hypomobility (four). Five examinations were repeated to determine intra-rater reliability. Participants were asked to judge if there was or there was no purposeful motion, as described by written definitions, for each vocal fold (800 tokens in total).

RESULTS: Twenty reviewers (100%) replied. Both general otolaryngologists and fellowship-trained laryngologists had an overall inter-rater reliability of 95%. Difference in inter-rater reliability between the two groups of raters was negligible: 95% for general otolaryngologists and 97.5% for fellowship-trained laryngologists. There was no variability in intra-rater reliability within either rater group (99%).

CONCLUSION: Intra- and inter-rater agreement in determining whether the patient had purposeful vocal fold motion on flexible laryngoscopic examination was excellent in both groups. This study demonstrates that otolaryngologists can consistently and accurately judge the presence and the absence of vocal fold motion.