Diagnostic accuracy of the Smoothed Cepstral Peak Prominence (CPPS) in the detection of dysphonia in the Spanish language

Abstract

The smoothed cepstral peak prominence (CPPS) is an acoustic measure that can be calculated in both sustained vowels and continuous speech. The goal of this work is to find out the diagnostic accuracy of CPPS in the detection of dysphonia in Spanish.
 In this study 136 subjects with dysphonia and 47 healthy subjects participated. For each subject a sustained vowel and the reading of three phonetically balanced sentences were recorded. The CPPS was calculated with Praat using its default configuration (configuration 1), and also with the one used in the calculation of the Acoustic Voice Quality Index (configuration 2). Five experts perceptively assessed the voice of the subjects in the sample by means of the GRABS scale.
 The CPPS has a great power of discrimination between the normal and the pathological voice, whether it is calculated from the sustained vowel /a/ (AROC[config. 1] = 0.863 and AROC[config. 2] = 0.841) or whether it is calculated from the sentences (AROC[config. 1] = 0.884 and AROC[config. 2] = 0.866).
 The results confirm that CPPS is a valid acoustic measurement to detect dysphonia in the Spanish language.

Cepstral Peak Prominence Values for Clinical Voice Evaluation

“…These thresholds are somewhat lower than ours, but our Experiment 1 cutoff values are intended to distinguish patients with voice disorders versus vocally healthy controls instead of mild versus severe dysphonia. Additionally, our Praat CPPS thresholds are similar to the ones identified by Delgado-Hernández et al (2019) , whose Praat “Configuration 2” settings yielded CPP thresholds of 13.96 dB for sustained vowels and 8.37 dB for continuous speech.…”

“…Studies by Núñez-Batalla et al (2019) and Delgado-Hernández et al (2019) used Praat's CPPS algorithm to investigate CPP in Spanish speakers with and without diagnoses of voice disorders. Núñez-Batalla et al identified normative CPPS values by computing the averages and standard deviations of the control groups' CPPS values for each task, rather than identifying threshold values to separate speakers with and without voice disorders.…”

“…Many of these findings in English speakers are reviewed by Fraile and Godino-Llorente (2014) , which also provides an overview of the algorithms underlying CPP computation. Other work has also examined CPP in languages other than English, including Spanish ( Delgado-Hernández et al, 2019 ; Núñez-Batalla et al, 2019 ), Korean ( Lee et al, 2019 ; Yu et al, 2018 ), and Turkish ( Aydinli et al, 2019 ). In general, these studies find that lower CPP values are well correlated with increases in dysphonia severity based on auditory-perceptual judgments.…”