# Pareto-Optimized AVQI Assessment of Dysphonia: A Clinical Trial Using Various Smartphones
## 3 Materials and Methods  
### Materials  
The study comprised 134 adult participants, with 58 men and 77 women, who were evaluated in the Department of Otolaryngology of the Lithuanian University of HealthSciences, Kaunas, Lithuania. The mean age of the participants was 42.9 (SD 15.26) years. The pathological voice subgroup, which included 86 patients (42 men and 44 women), had a mean age of 50.8 years (SD 14.3) and presented with a variety of laryngeal diseases and associated voice impairments, such as benign and malignant mass lesions of the vocal folds and unilateral paralysis of the vocal fold. Diagnosis was based on clinical examination, including patient complaints and history, voice assessment and video laryngostroboscopy (VLS) using an XION Endo-STROB DX device (XION GmbH, Berlin, Germany) 70\({}^{\circ}\) rigid endoscope and /or direct microlaryngoscopy. Five experienced physicians-laryngologists performed the auditory-perceptual evaluations of voice samples. For the purpose of this study, only the evaluation of dysphonia's grade (G) was used from the GRBAS scale (grade, breathiness, roughness, asthenia, and strain). The voice samples were rated into four ordinal severity classes of G on the scale from 0 to 3 points, where 0 = normal voice, 1--mild, 2--moderate, and 3--severe dysphonia [64]. A severity distribution is displayed in Figure 1.  
The normal voice subgroup consisted of 49 healthy volunteers, 16 men and 33 women, with a mean age of 31.69 (SD 9.89) years. To qualify as vocally healthy, participants were required to have no actual voice complaints, no history of chronic laryngeal diseases or voice disorders, and to self-report their voice as normal. The voices of the participants were evaluated as normal by otolaryngologists specialized in the field of voice, as there were no pathological alterations in the larynx. Demographic data for the study group and diagnoses for the pathological voice subgroup are presented in Table 1.  
Voice samples representing five different smartphones were used, namely the iPhone 12 Pro, iPhone 13 Pro Max, Xiaomi Redmi Note 5, iPhone 12 Mini, and Samsung Galaxy S10+. The following processing conditions were applied: smartphones were placed approximately 30.0 cm away from the mouth, at a 90\({}^{\circ}\) angle to the mouth, and had internal microphones (bottom) (see Figure 2). The devices were selected from a range of commercial prices. The background noise level averaged 29.61 dB SPL and the signal-to-noise ratio (SNR) was approximately 38.11 dB compared to the voiced recordings, indicating that the environment was suitable for both voice recordings and the extraction of acoustic parameters. The AKG microphone was placed 10.0 cm from the mouth at a comfortable (approximately 90\({}^{\circ}\)) microphone-to-mouth angle. Figure 1: Severity distribution of the patients involved. A phonetically balanced Lithuanian sentence \"Turejo senele zila ozeli\" (\"Old granny had a billy goat\") was the main utterance used to compare the recordings. The relative frequencies of the phonemes in the sentence are as close as possible to the distribution of speech sounds used in Lithuanian. The examples of spectral analysis results of voice samples are given in Figure 3. \begin{table}
\begin{tabular}{c c c c} \hline
**Diagnosis** & **Total** & **Age (mean)** & **Age (SD)** \\ \hline Normal voice & 49 & 31.69 & 9.89 \\ Vocal fold nodules & 6 & 42.67 & 10.86 \\ Vocal fold polyp & 21 & 40.95 & 12.98 \\ Vocal fold cyst & 3 & 42.67 & 12.58 \\ Vocal fold cancer & 11 & 65.09 & 7.71 \\ Vocal fold polypoid hyperplasia & 12 & 53.25 & 8.07 \\ Vocal fold keratosis & 4 & 56.25 & 2.63 \\ Vocal fold papilloma & 7 & 41.71 & 13.67 \\ Unilateral vocal fold paralysis & 6 & 40.83 & 12.77 \\ Bilateral vocal fold paralysis & 4 & 52.75 & 12.61 \\ Chronic hyperplastic laryngitis & 6 & 55.67 & 9.63 \\ Dysphonia & 1 & 22 &. \\ GERD & 2 & 57 & 15.56 \\ [PERSON]’s disease & 2 & 71.5 & 9.19 \\ \hline \end{tabular}
\end{table} 
Table 1: Demographic data of the study group.