Prospective pilot study of a smartphone app as a screening tool for unilateral vocal fold paresis/paralysis.

PURPOSE: Low-cost tools are needed to differentiate normal from abnormal vocal fold mobility in resource-limited settings or in absence of laryngoscopic examination tools. METHOD: This is a prospective observational pilot study. Acoustic samples were recorded on the OperaVOX app to detect unilateral vocal fold paralysis/paresis (UVFP). RESULTS: Seventy participants were enrolled in two parallel cohorts (37 cases, 33 controls), 43 (61.4%) were females. Comparing cases to controls, there were significant differences in F2, jitter, shimmer, shimmer (dB), and harmonic to noise ratio (HNR), (P < 0.05). Multiple parameters demonstrated moderate accuracy (area-under-the-curve (AUC) > 0.7) in all patients, females and male. Logistic regression identified parameters that significantly predicted UVFP in all patients, females-only and males-only. Lastly, multiple cut-off values with variable sensitivity/specificity performances were identified to support the use of OperaVOX as a screening tool based on the logistic regression results. CONCLUSIONS: This pilot study identified cutoff values of acoustic parameters collected by OperaVOX with sensitivity/specificity as a potential screening tool for dysphonia to identify patients to be referred for laryngeal examination. Future studies in resource-limited-settings are needed to validate our results.