RESUMEN
OBJECTIVE: The goal of this study is to analyze the voice in patients with thyroid pathology through two objective indexes with great diagnostic accuracy. Overall vocal quality was evaluated with the Acoustic Voice Quality Index (AVQI v.03.01) and the breathy voice with the Acoustic Breathiness Index (ABI). DESIGN: Observational case-control study. SETTING: Hospital Universitario Nuestra Señora de Candelaria. PARTICIPANTS: Fifty-eight subjects, 29 controls and 29 thyroidectomy candidates. MAIN OUTCOME MEASURES: All participants with thyroid pathology completed the Spanish version of Voice Handicap Index-10. Also, patient complaints relating to possible laryngeal dysfunction were assessed through closed questions. A sustained vowel and three phonetically balanced sentences were recorded for each subject (118 samples). AVQI v.03.01 and ABI were assessed using the Praat program. Two raters perceptually evaluated each voice sample by using the Grade parameter of GRABS scale. RESULTS: Acoustic analysis shows that 55.17% of subjects present values above the pathological threshold of the AVQI, and 58.62% above that of the ABI. Results of the Student's test comparisons of the AVQI and ABI values between the control group and the thyroid group show significantly higher values of AVQI (t[56] = -3.85, p < .001) and ABI (t[54.39] = -4.82, p < .001) in thyroidectomy candidates. CONCLUSION: A mild decrease in vocal quality is part of the symptomatology presented by thyroidectomy candidates.