Multidimensional Voice Outcomes After Individualized Voice Therapy in Women with Vocal Fold Nodules: A Retrospective...

This study aimed to evaluate changes in voice quality following individualized voice therapy in women with vocal fold nodules (VFNs), using a multidimensional assessment approach incorporating both conventional acoustic parameters and advanced cepstral measures, including Cepstral Peak Prominence Smoothed (CPPs) and Acoustic Voice Quality Index (AVQI).

In this retrospective controlled study, 35 adult female patients with VFNs who underwent voice therapy and 35 age-matched healthy female controls were included. Voice assessment included perceptual measures (GRBAS), patient-reported outcomes (T-VHI-10), aerodynamic parameters (MPT, s/z ratio), and acoustic/cepstral measures (F0, jitter, shimmer, NHR, AVQI, CPPs-SV, CPPs-CS). Recordings were analyzed using sustained vowel and connected speech samples, and statistical analyses were conducted using nonparametric tests with Holm-Bonferroni correction applied for multiple comparisons.

Significant improvements were observed in all perceptual and patient-reported outcomes (GRBAS, T-VHI-10; P < 0.001) and in aerodynamic measures (MPT, s/z ratio; P < 0.01) following therapy. Acoustic and cepstral parameters, including jitter, shimmer, NHR, AVQI, CPPs-SV, and CPPs-CS, also showed significant improvements (P < 0.01), whereas F0 remained unchanged (P = 0.376). Posttherapy comparisons with controls indicated that s/z ratio, jitter, AVQI, and CPPs-SV did not differ significantly between groups, while MPT, GRBAS, T-VHI-10, CPPs-CS, and selected acoustic parameters remained significantly different (P < 0.05).

Individualized voice therapy leads to significant multidimensional improvements in women with VFNs. Cepstral and perceptual measures are sensitive to therapeutic change, while persistent differences in connected speech measures suggest the need for further enhancement of functional voice generalization.