Exploring the Relationship Between Spectral and Cepstral Measures of Voice and the Voice Handicap Index (VHI)

Objectives. The purpose of this study was to examine the strength of relationship between impairment-level acoustic measures derived from spectral-and cepstral-based analyses (including the cepstral peak prominence [CPP]; ratios of low vs high frequency spectral energy; and the respective standard deviations [SDs] for these measures) and a disablement measure (the total Voice Handicap Index [VHI] score) in a large and diverse group of voice-disordered and control subjects. The relationship between total VHI and the Cepstral Spectral Index of Dysphonia (CSID-a multivariate estimate of dysphonia severity) was also examined. Methods. Subjects were 332 adults (116 males and 216 females) comprised of voice-disordered subjects who presented to a physician with a voice-related complaint (n = 258) and a group of nonvoice-disordered control subjects (n 74). AVHI 30-item score and speech/voice samples including the second and third sentences of The Rainbow Passage and productions of the sustained vowel /a/ were obtained for each subject. Sentence and sustained vowel samples were analyzed using the Analysis of Dysphonia in Speech and Voice (ADSV) program (ADSV model 5109 v. 3.4.2; KayPENTAX, Montvale, NJ). Results. Across all subjects, low-to-moderate strength Spearman rho (r(s)) correlations were observed between the total VHI and the CPP and the CSID in both speech and vowel contexts and for the CPP SD from continuous speech (r(s)'s ranging from -0.45 to -0.49 for VHI vs CPP; 0.47 for VHI vs CSID; -0.44 for VHI vs CPP SD). Several other measures obtained from spectral or cepstral analyses also were observed to correlate with total VHI, although increased variability in the strength, direction, and overall significance of these other variables was observed depending on gender and elicited context. Conclusions. Voice-related disablement occurs within a context. In contrast, impairment-level measures of phonatory function (like the spectral and cepstral measures included in this study) are by nature decontextualized and appear to correlate low-to-moderately with quality of life measures like the VHI. Therefore, spectral and cepstral acoustic measures and the VHI should be viewed as providing relatively unique, meaningful, and complementary information.