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Characteristics of the Voice of Dysphonic School Children from 4:0 to 7:11 Years Old
ARTICLE IN PRESS
Characteristics of the Voice of Dysphonic School Children from 4:0 to 7:11 Years Old Carla Franco Hoffmann, and Carla Aparecida Cielo, Santa Maria, Brazil Summary: Background. Childhood dysphonia is frequent and has many origins, with the most common initial symptom being the altered vocal quality. Objective. Describe and correlate the auditory-perceptual and acoustic characteristics of the voice, and the maximum phonation time (MPT), of dysphonic schoolchildren from private and public schools from 4:0 to 7:11 years old, female and male. Methods. MPT, acoustic (Multi-Dimensional Voice Program Advanced and Real Time Spectrogram), and auditory-perceptual (Consensus Auditory-Perceptual Evaluation of Voice) evaluations of 115 schoolchildren were statistically analyzed. Results. Auditory-perceptual parameters values were classified as mild, and MPT values were reduced, in most children. Fundamental frequency and Jitt values decreased significantly with age; MPT/i/ increased significantly with age. Relative average perturbation, voice turbulence index (VTI), and number of sub-harmonic segments values were significantly higher in 4:0 years old children. The number of unvoiced segments was higher in 6:0 years old children. Shimmer percent was higher in 7:0 years old children. There were negative correlations between the high frequency spectrographic tracing color intensity and the vocal strain; the VTI and the MPT; the degree of unvoiced segments and the MPT. There was a positive correlation between the smoothed pitch period perturbation quotient and the roughness. Conclusion. In dysphonic schoolchildren, auditory-perceptual parameters were moderate, MPT was reduced, several acoustic parameters were altered, and these vocal characteristics improved with age. Key Words: Larynx−voice−Voice quality−Child−Speech−Language and hearing sciences.
INTRODUCTION Childhood dysphonia is frequent and has many origins, with the most common initial symptom being the altered vocal quality. Parents or guardians may not detect this symptom, as they are used to the vocal characteristics of their children, so it may be detected first outside the family context.1 Children 4:0−7:11 years old may be identified as dysphonic for the first time by their teachers at school, outside of their home environment.1 Late detection of the abnormal vocal qualities may delay dysphonia identification and intervention, with consequences to the children. Even dysphonic children that are aware of their vocal limitation may not be able to express their frustration. In such cases, the voice can be used to express aggressiveness or to relieve stress by screaming, mainly while playing with other children.2−4 Also, introvert or repressed children, or the ones that find it difficult to socialize with other children, may have an increased muscular internal stress stored in the larynx and dysphonia.2,4 Childhood dysphonia may influence the perception of other children or adults. In a recent research, dysphonic children were described as “dirty,” “weak,” “sick,” or “ugly.”1 A survey analyzing parents of children and teenagers 6:0−18:0 years old showed that the group with vocal Accepted for publication December 2, 2019. From the Departamento de Fonoaudiologia, Universidade Federal de Santa Maria, Santa Maria, RS, Brazil. Address correspondence and reprint requests to Carla Aparecida Cielo, Departamento de Fonoaudiologia, Universidade Federal de Santa Maria, Santa Maria, RS 97105-900, Brazil. E-mail: [email protected] Journal of Voice, Vol. &&, No. &&, pp. &&−&& 0892-1997 © 2019 The Voice Foundation. Published by Elsevier Inc. All rights reserved. https://doi.org/10.1016/j.jvoice.2019.12.004
complaints presented risk of developing behavioral problems.5 Childhood dysphonia may also influence the choice of profession; children that lived negative experiences related to their voices may avoid working in professional classes that use the voice directly.2 Children’s voices presenting a mild degree of roughness or breathiness were considered nondysphonic.6−11 The maximum phonation time (MPT) value measured in seconds is equal to the age value measured in years for nondysphonic children,9−12 but in dysphonic children the MPT value is smaller than the age value.7 Also, in nondysphonic children the jitter, shimmer,7,13−15 and the fundamental frequency (F0)15,16 decrease with age. Some studies analyzed the voice, the social skills, the vocal habits, and the auditory processing of dysphonic and nondysphonic children.7,14,17 Other studies measured the prevalence of childhood dysphonia found to be within 6%−23%.8,10,18 Few studies described the vocal characteristics of dysphonic children6,19; this is the aim of our study. It is relevant to characterize the voice of dysphonic children. It is important to gather results from different vocal assessment procedures, and check how they correlate, so the diagnosis is more accurate, and the treatment is more effective. Our study aims at identifying and correlating the auditory-perceptual and acoustic vocal characteristics, and the vowels’ MPTs of dysphonic children 4:0−7:11 years old.
METHODS Ethical aspects The Research Ethics Committee of the authors’ institution approved this study (0306.0.243.000-10). All children orally
ARTICLE IN PRESS 2 stated their agreement to participate in the research, and their parents signed the Informed Consent, and all schools signed the Institutional Authorization Term. Research characteristics This is a contemporary, cross-sectional, analytical, quantitative study using data collected from students in public or private schools from a medium sized city with 280,505 inhabitants. Schools’ randomization A list containing the names of all the 104 schools in alphabetical order was constructed, and every third name was excluded in order to have a randomized list of schools; children from the excluded schools did not participate in this study. The Institutional Authorization Term was sent to the final list. Participants’ selection The parents answered the medical history interview regarding the anthropometric data, health history, and the development of the child. Afterwards, an auditory screening and a voice evaluation were performed in the child. Inclusion criterium was dysphonic child 4:0−7:11 years old. This criterium was chosen in order to exclude factors related to neuromuscular immaturity present in children less than 4:0 years old, or factors related to hormonal development that may be present in children more than 8:0 years old. Exclusion criteria were: report from the parents or guardians of delayed neuropsychomotor development, of psychological, psychiatric, postural, or pulmonary alterations, of syndromes; severe physical handicap or structural alterations that could compromise phonation at respiratory, phonatory, or articulatory levels; being under speech-language therapy for the voice at the time of data collection, or having done it previously to avoid interference of vocal training on vocal characteristics; surgery in orofacial region; influenza or respiratory allergies in the day of the evaluations.20 None of the participants had been previously evaluated for concerns of abnormal vocal qualities or have a known medical diagnosis related to their dysphonia. To exclude children with suspected hearing loss, an auditory screening was performed by a speech therapist21 within the 1−4 kHz frequency range at 20 dB, by air (audiometer Amplivox, model 2011, type A260), in a quiet environment with noise level (measured with Instrutherm model Dec-480) below 50 dBNPS (Res. 274/01−Brazilian Federal Council of Speech, Language and Hearing Sciences). For the classification of dysphonic voice (inclusion criterium) and nondysphonic voice, also by speech therapist,21 “equally spaced” version of Consensus Auditory-Perceptual Evaluation of Voice (CAPE-V)22 was used, adapted for Portuguese.23 Using sustained emissions, phrase repetitions, and spontaneous speech, the CAPE-V allows one to measure aspects of the
Journal of Voice, Vol. &&, No. &&, 2019
vocal quality such as overall severity of dysphonia, roughness, breathiness, strain, pitch, loudness, and resonance. CAPE-V is composed of a linear analogue scale ranging from 0 to 100 mm, for each parameter. The parameters pitch, loudness, and resonance were not measured in this study. Those children who presented an overall severity greater than moderate (from 50%) were considered dysphonic. There could be numerous etiologies for the dysphonia described here, except those due to the exclusion criteria. Considering the children’s population of the city within the 4:0−7:11 age range (20,717), to obtain a 95% significance level, a sample of 237 children was necessary. A total of 1015 IC were distributed, and 427 were signed and returned authorizing the child’s participation in the study. One hundred ninety-two children were excluded for presenting normal voice or a mild level (up to 10%) of dysphonia; 97 children were excluded for being more than 7:11 years old; 15 children were excluded for having respiratory allergy in the day of the evaluations; 5 children were excluded for having pulmonary alteration; and 3 children were excluded for being reported with delayed neuropsychomotor development. The final sample was composed of 115 children, that were divided into four groups; group I: 19 children 4:0−4:11 years old; group II: 24 children 5:0−5:11 years old; group III: 33 children 6:0−6:11 years old; group IV: 39 children 7:0−7:11 years old. DATA COLLECTION Each child sustained MPT/a/, /i/, and /u/ after taking deep breath, in regular pitch, loudness, and vocal quality.12,20,24,25 The tongue is at a different position during the emission of each of these vowels (the vowel triangle), so differences in the vocal tract impedance may cause differences among MPTs. Three measurements of each MPT vowel were timed in seconds, and the longest time was considered.12,24,25 To sample the spontaneous speech, each child talked about what he/she liked to do during recess, and about his/her thoughts on his/ her own voice. Also, they repeated all CAPE-V phrases. All recordings were performed before recess and physical education classes to avoid interference from the intensive and/or abusive use of the voice, and at only one occasion. To record the vocal emissions, a professional digital recorder Zoom model H4n was used, 16 bit audio format pulse-code modulation, 96-kHz sampling frequency, Behringer ECM 8000 omnidirectional microphone with a flat band frequency range from 15 to 20 kHz, positioned horizontally in front of the child's mouth, at a fixed distance of 4 cm for the MPT recording, and at a fixed distance of 10 cm for the spontaneous speech and phrases. The recording sessions took place in a room with ambient noise of less than 50 dBNPS, measured using a digital sound pressure level meter model Dec-480.20 Three judges with more than 3 years of experience in voice evaluated, individually, the auditory-perceptual characteristics of the 115 children’s voices.20 The judges were instructed on the CAPE-V scale parameters and their
ARTICLE IN PRESS Carla Franco Hoffmann and Carla Aparecida Cielo
Characteristics of the Voice of Dysphonic School Children
marking, considering parameters roughness, breathiness, strain, and overall severity of dysphonia.8,20,21,25 For the statistical calculations, the arithmetic mean of the evaluations of the judges in each of the CAPE-V protocol items was considered.8,20,24,25,26 In the acoustic vocal evaluation, the unstable initial and final portions of the emission of MPT/a/ were removed, so instabilities in the vocal signal are avoided and do not influence data analysis.8,24,27 The shortest MPT/a/ time among all subjects was 3 seconds, determined by the time window acoustic analysis.12,28 Detailed editing specifications are described below. In the acoustic analysis of the glottal signal, the Kay Pentax Multi-Dimensional Voice Program Advanced (MDVPA) was used with 44 kHz sampling rate and 16 bits analog-digital conversion. Each parameter analysis was based in several measurements: frequency measurements: fundamental frequency (f0), f0 high (fhi), f0 low (flo), standard deviation of f0 (STD); frequency perturbation measurements: absolute jitter (Jita), jitter percent (Jitt), relative average perturbation (RAP), pitch perturbation quotient (PPQ), smoothed pitch perturbation quotient (sPPQ), f0 variation (vf0); amplitude perturbation measurements: shimmer in dB (ShdB), shimmer percent (Shim), amplitude perturbation quotient (APQ), smoothed amplitude perturbation quotient (sAPQ), peak-topeak amplitude variation; noise measurements: noise to harmonic ratio, voice turbulence index (VTI), soft phonation index; voice break measurements: degree of voice breaks, number of voice breaks; unvoiced segments measurements: number of unvoiced segments (NUV), degree of unvoiced segments (DUV); sub-harmonic segments measurements: degree of sub-harmonic components, number of sub-harmonic segments. In the spectrographic voice acoustic analysis the Kay Pentax Real Time Spectrogram was used to generate broadband spectrogram (BBS) filtered in 100 points (646 Hz) and narrowband spectrogram (NBS) filtered with 1024 points (63.09 Hz), with 11 kHz sampling rate, 16 bits analog-digital conversion, and 5 kHz window. The spectrographic analysis was performed by four speech therapist judges (different from the judges who performed the CAPE-V evaluation) with more than three years of experience in voice acoustic analysis, using a specific protocol created by the authors (to be published). The judges received two standard normal voice spectrograms to guide their judgment, one BBS and one NBS.29 The judges also received the 115 subjects’ BBS and NBS of the vowel /a/ without the vocal auditory signal, to avoid its influence on the judgment.29 It was considered the predominant opinion among the judges for each item of the protocol. In exceptional cases where no agreement was obtained, a fifth judge was consulted. The judges were blinded to the objective of the study, age, and gender of the children; they are not authors of this study.27,29 In the BBS the following parameters were evaluated: tracing color intensity of the formants F (F1, F2, F3, and F4); tracing color intensity at high frequencies; tracing color
3
intensity in the entire vocal spectrogram; noise at high frequencies; noise in the entire vocal spectrogram; definition of F; regularity of the tracing. In the NBS, the following parameters were evaluated: tracing color intensity at high frequencies; tracing color intensity in the entire vocal spectrogram; noise between the harmonics at high frequencies; noise between the harmonics in the entire vocal spectrogram; replacement of harmonics by noise at high frequencies; replacement of harmonics by noise in the entire vocal spectrogram; definition of harmonics; regularity of the tracing; number of harmonics; presence of subharmonics. Data analysis We used the Kruskall-Wallis nonparametric test to compare age groups I, II, III, and IV. The correlations among the results from MPT, MDVPA, CAPE-V, BBS, and NBS, were tested using the Spearman correlation coefficient. The significance level of 5% was adopted in all tests. RESULTS The Spearman correlation coefficient showed significant negative correlation between: auditory-perceptual parameter strain and NBS tracing color intensity at high frequencies (r = 0.7); auditory-perceptual parameter strain and BBS tracing color intensity at high frequencies (r = 0.6); VTI and MPT/i/ (r = 0.8); DUV and MPT/a/ (r = 0.7); DUV and MPT/i/ (r = 0.6); DUV and MPT/u/ (r = 0.8). It showed significant positive correlation between the auditory-perceptual parameter roughness and sAPQ (r = 0.9). No other significant correlations were observed. DISCUSSION The MPT increased with age, with significance for MPT/i/. Group IV sustained vocal emission for longer (Table 1). According to references,10,27 the MPT in seconds is proportional to the children’s age in years; this fact can be attributed to the laryngeal anatomophysiological development and to the neurological maturation during childhood.9,10,12 When compared to other studies on children with normal voice,10,12 the MPT in our study is reduced, as expected for dysphonic children.7 A study with 60 children and teenagers with normal voice and ages within the 6:0−17:11 years age range, found that the group with ages from 6:0 to 9:11 years had MPT of 11.3 s for girls and of 12.5 s for boys.11 A study with 75 singer and nonsinger children and ages within the 6:0 to 13:0 years age range, found an average MPT of 15.9 s for nonsingers and of 15.4 s for singers, concluding that singing practice did not influence MPT.9 Regarding the auditory-perceptual analysis, some authors consider the presence of roughness and breathiness in the child’s voice as normal, and other authors consider it as a pathological sign depending on the degree.8 In our study we considered a mild degree (up to 10%) of roughness and breathiness as normal in the child’s voice,6,10 as these are the most common characteristics in children. Most dysphonic
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TABLE 1. Maximum Phonation Time Comparison Among Groups I−IV GI (4−4:11 yo)
DP
GII (5−5:11 yo)
DP
GIII (6−6:11 yo)
DP
GIV (7−7:11 yo)
DP
P Value
4.90 4.71 3.93
0.75 0.25 0.55
5.30 5.28 4.55
0.84 0.75 0.72
5.66 5.79 5.33
0.15 0.19 0.23
6.40 7.09 6.51
0.21 0.42 0.84
0.56 0.01* 0.08
TMF/a/ (s) TMF/i/ (s) TMF/u/ (s)
* Data statistically significant (P < 0.05). Kruskall-Wallis test. There was difference among the groups for MPT/i/. Abbreviations: G, group; SD, standard deviation; yo, years old; MPT, maximum phonation time.
children in our study, of all ages, presented moderate degree of overall severity and of all the other vocal parameters (roughness, breathiness, and strain), with statistical significance and showing the presence of dysphonia (Table 2). A study Kallvik et al with 217 children within the 6:0−10:0 years age range questioned parents and teachers on the children’s vocal quality and correlated this data with the CAPE-V data, founding roughness as the most frequent vocal characteristic.18 A study from Diercks et al concluded that auditory-perceptual vocal evaluation is a reliable method, as the results were the same for measurements made at two different times.30 Another study from Tezcaner et al found that the auditory-perceptual vocal evaluation is a reliable method to follow the vocal changes during therapy of dysphonic children within the 7:0−14:0 years age range.15 F0 e Jitt decreased significantly with age. RAP, VTI, and number of sub-harmonic segments were significantly higher for children 4:0 years old, NUV was significantly higher for children 6:0 years old, and Shim was significantly higher for children 7:0 years old (Table 3). F0 values for groups I−IV were 268.1 Hz, 255.0 Hz, 253.1 Hz, and 241.3 Hz, respectively (Table 3); F0 is expected to decrease with age, due to body growth.31 In our study we found F0 values lower in dysphonic children than the ones found in studies with nondysphonic children.10,21,32 This may suggest the existence of increased vocal folds’
mass due to edema or vocal nodule, a common laryngeal pathology in children within the studied age range.7,21,29 In a study from Tavares et al with boys and girls aged 4:0−7:0 years, F0 for girls within the 4:0−5:0 years age range was 275 Hz, and for boys and girls within the 6:0−7:0 years age range they were 243.37 Hz and 258.03 Hz, respectively.10. In a study from Braga et al with nondysphonic children, F0 was 263.65 Hz for children 6:0 years old, and 250.55 Hz for children 7:0 years old.32 In a study from Viegas et al with children within the 6:0−7:0 years age range, F0 was 258 Hz.21 In another study from Brockmann-Bauser et al with 68 nondysphonic children within the 5:0−9:11 years age range, F0 was 276 Hz for girls and 261 Hz for boys.16 In a study from Nicollas et al with 212 nondysphonic children within the 6:0−9:0 years age range, F0 decreased with age; jitter and shimmer also decreased with age, but not with statistical significance.7 This behavior was also found in our study where F0 and Jitt significantly decreased with age. Another study from Maturo et al with 336 nondysphonic children found that both boys and girls within the 4:0−12:0 years age range had the same vocal profile; F0 was 279 Hz and shimmer and jitter values were similar to the values found in adults.14 A study from Valadez et al with 20 children with vocal nodules found significantly different acoustic vocal
TABLE 2. CAPE-V Comparison Among Groups I−IV Parameter Overall severity Roughness Breathiness Strain
M S M S M S M S
G I (4−4:11 yo) (n)
(%)
GII (5−5:11 yo) (n)
(%)
GIII (6−6:11 yo) (n)
(%)
GIV (7−7:11 yo) (n)
(%)
P Value
16 3 15 4 19 0 19 0
84.21 15.78 78.94 21.05 100 0 100 0
21 3 22 2 24 0 24 0
87.5 12.5 91.66 8.33 100 0 100 0
30 3 29 4 30 3 33 0
90.09 9.9 87.98 12.12 90.9 9.09 100 0
34 5 37 2 39 0 39 0
89.75 12.82 94.87 5.12 100 0 100 0
0.89
Kruskall-Wallis test. The data in this table are not statistically significant. Abbreviations: G, group; SD, standard deviation; yo, years old; n, number of subjects; %, percentage of subjects; M, moderate; S, severe.
0.31 0.28 0.49
Frequency measurements Frequency perturbation measurements
Voice breaks measurements Unvoiced segments measurements Sub-harmonic segments measurements
DP
GII (5−5:11 yo)
DP
GIII (6−6:11 yo)
DP
GIV (7−7:11 yo)
DP
P Value
268.1 11.5 66.7 2.4 1.7 1.8 3.8 5.3 1.3 6.2 4.4 5.9 19.3 0.2 0.1 3.3 1.5 5.8 3.0 9.5 5.6 5.1
0.15 0.16 0.15 0.23 0.22 0.17 0.33 0.24 0.15 0.15 0.17 0.18 0.22 0.17 0.26 0.27 0.23 0.27 0.28 0.25 0.15 0.16
255.0 14.2 115.3 1.9 1.1 1.2 1.0 6.1 0.8 5.3 4.3 4.8 15.7 0.2 0.1 ; 0.1 2.7 2.7 3.8 2.6 3.1
0.25 0.17 0.18 0.21 0.26 0.24 0.16 0.19 0.18 0.22 0.25 0.15 0.17 0.29 0.24 ; 0.15 0.17 0.18 0.15 0.18 0.19
253.1 9.4 72.4 1.8 1.1 1.1 1.2 3.4 0.5 6.1 4.3 6.2 19.2 0.2 0.6 4.7 0.0 3.2 3.7 0.5 4.2 4.1
0.24 0.16 0.18 0.22 0.25 0.27 0.25 0.15 0.23 0.16 0.15 0.17 0.26 0.18 0.25 0.21 0.18 0.15 0.23 0.25 0.15 0.19
241.3 17.5 90.0 1.2 1.3 1.4 2.5 6.8 0.6 7.2 5.1 6.7 20.9 0.2 0.5 3.8 0.4 5.7 1.1 2.1 3.0 2.8
0.25 0.24 0.21 0.15 0.17 0.18 0.15 0.17 0.21 0.17 0.15 0.25 0.27 0.22 0.15 \ 0.21 0.16 0.15 0.24 0.21 0.28
0.01* 0.17 0.85 0.03* 0.03* 0.45 0.71 0.41 0.22 0.02* 0.75 0.64 0.06 0.05 0.02* 0.95 0.37 0.68 0.03* 0.52 0.07 0.04*
* Data statistically significant (P < 0.05). Kruskall-Wallis test. Abbreviations: G, group; SD, standard deviation; yo, years old; %, percentage; f0, fundamental frequency; fhi, f0 high; flo, f0 low; STD, standard deviation of f0; Jita, absolute jitter; Jitt, jitter percent; RAP, relative average perturbation; PPQ, pitch perturbation quotient; sPPQ, smoothed pitch perturbation quotient; vf0, f0 variation; ShdB, shimmer in dB; Shim, shimmer percent; APQ, amplitude perturbation quotient; sAPQ, smoothed amplitude perturbation quotient; vAm, peak-to-peak amplitude variation; NHR, noise to harmonic ratio; VTI, voice turbulence index; SPI, soft phonation index; DVB, degree of voice breaks; NVB, number of voice breaks; NUV, number of unvoiced segments; DUV, degree of unvoiced segments; DSH, degree of sub-harmonic components; NSH, number of sub-harmonic segments.
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Noise measurements
GI (4−4:11 yo)
Characteristics of the Voice of Dysphonic School Children
Amplitude perturbation measurements
F0 (Hz) STD (Hz) Jita (us) Jitt (%) RAP (%) PPQ (%) sPPQ (%) vF0 (%) Shdb (dB) Shim (%) APQ (%) sAPQ (%) vAm (%) NHR VTI SPI DVB (%) NVB (%) NUV (%) DUV (%) DSH (%) NSH (%)
Carla Franco Hoffmann and Carla Aparecida Cielo
TABLE 3. Multi-Dimensional Voice Program Advanced Comparison Among Groups I−IV
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TABLE 4. Broadband Spectrograms Comparison Among Groups I to IV Parameters Tracing color intensity F1
Weak Medium Strong Tracing color Weak intensity F2 Medium Strong Tracing color Weak intensity F3 Medium Strong Tracing color Weak intensity F4 Medium Strong Tracing color intensity Weak at high frequencies Medium Strong Tracing color intensity Weak in the entire Medium spectrogram Strong Noise in the entire Absent spectrogram Barely present Present Noise at high Absent frequencies Barely present Present Definition of F1 Absent Barely defined Defined Definition of F2 Absent Barely defined Defined Definition of F3 Absent Barely defined Defined Definition of F4 Absent Barely defined Defined Regularity of Low the tracing Medium High
GI (4−4:11 GII (5−5:11 GIII (6−6:11 GIV (7−7:11 yo) (n) (%) yo) (n) (%) yo) (n) (%) yo) (n) (%) P Value 2 8 9 4 10 5 10 5 4 12 2 5 8 9 2 5 0 14 0 1 18 0 1 18 4 6 9 8 7 4 16 3 0 15 4 0 13 6 0
11 42 47 21 53 26 53 26 21 63 11 26 42 47 11 26 0 74 0 5 95 0 5 95 21 32 47 42 37 21 84 16 0 79 21 0 69 31 0
0 15 9 3 13 8 15 5 4 20 2 2 11 7 6 14 3 7 19 5 0 0 5 19 7 11 6 12 9 3 16 8 0 22 2 0 15 9 0
0 62 38 13 54 33 62 21 17 84 8 8 46 29 25 58 13 29 79 21 0 0 21 79 29 46 25 50 38 12 67 33 0 92 8 0 63 37 0
9 15 9 14 5 14 27 1 4 25 2 6 14 13 6 0 8 25 0 8 25 31 2 0 8 20 5 18 12 3 27 6 0 31 2 0 22 11 0
27 46 27 42 16 42 84 3 13 76 6 18 43 39 18 0 24 76 0 24 76 94 6 0 24 61 15 55 36 9 81 19 94 6 0 67 33 0
7 17 15 0 30 9 24 10 5 16 22 1 7 25 7 12 14 13 2 9 28 32 7 0 9 20 10 18 6 15 32 7 0 35 4 0 20 19 0
18 44 38 0 77 23 61 26 13 41 56 3 18 64 18 31 36 33 5 23 72 82 18 0 23 51 26 47 15 38 82 18 0 90 10 0 51 49 0
0.89
0.56
0.25
0.1
0.76
0.33
0.12
0.15
0.35
0.21
0.1
0.35
0.15
Kruskall-Wallis test. The data in this table are not statistically significant. Abbreviations: G, group; SD, standard deviation; yo, years old; n, number of subjects; %, percentage of subjects; F, formant.
parameters when comparing to nondysphonic children, for example decreased values of F0 and increased values of shimmer and jitter,33 in accordance with our study. In another study from Tezcaner et al with dysphonic children within the 7:0−14:0 years age range, before voice therapy F0 was 275 Hz, Jitt was 2.51%, and Shim was 6.39%; and after voice therapy all values decreased.15 In our study, Shim was higher for children 7:0 years old (Table 3), in disagreement with studies with nondysphonic children.7,10 This measurement is related to the vocal amplitude variation periodicity, that may be related to the presence
of noise in the emission, mainly breathiness. This finding, due to its significance, characterized 7:0 years old dysphonic children in our study. In a study from Brockmann-Bauser et al with average 7:6 years old nondysphonic children Shim was 9.5%, higher than in our study, and Jitt was 0.5%.16 In another study from Guzman et al with average 8:10 years old nondysphonic children, within the 7:0−10:0 years age range, average shimmer was 8.04% for boys and 7.12% for girls, and jitter was 0.56% for boys and 0.48% for girls.13 In both studies jitter values were lower than the values found in our
Tracing color intensity in the entire vocal spectrogram
Noise between the harmonics in the entire spectrogram Definition of harmonics
Regularity of the tracing
GII (5−5:11 yo)
(%)
GIII (6−6:11 yo)
(%)
GV (7−7:11 yo)
(%)
P Value
15 4 0 15 4 0 12 3 4 18 1 0 13 6 0 12 4 3
79 21 0 79 21 0 63 16 21 95 5 0 68 32 0 63 21 16
20 4 0 19 5 0 15 5 4 18 3 3 22 2 0 12 8 4
83 17 0 79 21 0 62 21 17 76 13 13 92 8 0 50 33 17
17 13 3 25 8 0 21 10 2 13 15 5 21 10 2 33 0 0
52 39 9 76 24 0 64 30 6 39 46 15 64 30 6 100 0 0
30 9 0 25 10 4 21 12 6 17 13 9 29 10 0 21 15 3
77 23 0 64 26 10 54 31 15 44 33 23 74 26 0 54 38 8
0.87
Kruskall-Wallis test. The data in this table are not statistically significant. Abbreviations: G, group; SD, standard deviation; y, years; n, number of subjects; %, percentage of subjects.
0.96
0.67
0.89
0.08
0.07
Characteristics of the Voice of Dysphonic School Children
Noise between the harmonics at high frequencies
Weak Medium Strong Weak Medium Strong Absent Barely present Present Absent Barely present Present Absent Barely present Present Low Medium High
(%)
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Tracing color intensity at high frequencies
GI (4−4:11 yo)
Carla Franco Hoffmann and Carla Aparecida Cielo
TABLE 5. Narrowband Spectrograms Comparison Among Groups I−IV
7
ARTICLE IN PRESS 8 study with dysphonic children. In children 6:0 years old, NUV value was higher, suggesting the presence of noise in the emission. To verify this behavior, we suggest a study using a larger sample size, as it is observed a peak in the occurrence of vocal nodules within this age range, a common pathology in schoolchildren.1,2,31,33 The spectrographic voice acoustic data had no statistically significant differences among age groups. For BBS in most children, trancing color intensity of F and at high frequencies was weak or medium; noise in the entire vocal spectrogram was present; noise at high frequencies was present; definition of F was barely present or absent; and regularity of the tracing was low or medium (Table 4). For NBS in most children, tracing color intensity at high frequencies and in the entire vocal spectrogram was weak; noise between the harmonics at high frequencies and in the entire spectrogram was absent; definition of harmonics was absent; and regularity of the tracing was low (Table 5). These findings corroborate the auditoryperceptual findings of dysphonia with roughness, breathiness, and strain in a moderate degree. There was negative correlation between tracing color intensity at high frequencies (from both BBS and NBS) and the auditory-perceptual parameter strain. As the tracing color intensity is related to the sound pressure level and to the voice projection, the vocal productions with strain had low harmonic energy at high frequencies and weak vocal projection.29. The higher the VTI (noise in the vocal production), the shorter the MPT/i/; the higher the DUV (interruption in the sound wave, resulting in irregularity or noise in the vocal production), the shorter the MPT/a,i,u/. Acoustic measurements reflect the vocal behavior at the glottal level, while MPT measurements reflect the relation between the muscular and muco-undulatory action of the vocal folds, and the air flow from the lungs.31,33 Our results show that the presence of acoustic noise, common in dysphonic children, is related to the shortening of the MPT.7,10 There was positive correlation between sAPQ and roughness (caused by the aperiodic vibration of the vocal folds). Measurements of amplitude perturbation or shimmer, as sAPQ, indicate the periodicity of the vocal folds’ vibration cycles. Consequently, the values of sAPQ indicate their degree of stability and amount of harmonic energy. According to the study from Beber et al, an increase in the value of the shimmer parameter suggests acoustic noise in the vocal production, characterized by roughness, breathiness, or hoarseness.34 A study from Lopes et al evaluated 71 children within the 3:0−9:0 years age range and found a mild level of the auditory-perceptual vocal characteristics strain, instability, and breathiness, and positive correlation between F0 and strain, and between roughness and instability.6 These results are similar to the results found in our study. According to the study from Ma et al, the mean attitude ratings received by 6 children with dysphonic voice were significantly lower (ie, less favorable) than those received by
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children with healthy voices. This indicates that the results from our study may be also important to help dysphonic children fight against social stigma.35 The results from our study on the characteristics of the voice of dysphonic children may help early screening and identification of childhood dysphonia, and intervention. It will avoid the harmful consequences of dysphonia1,2,5 in child development. CONCLUSION Dysphonic children presented moderate degree alterations in auditory-perceptual parameters, and reduced MPT. Fundamental frequency decreased with age and was lower than nondysphonic children’s fundamental frequency. Acoustic alterations were more present in 4:0-year-old children. The spectrographic tracing color intensity at high frequencies decreased with vocal strain; MPT decreased with the increase in the presence of some noise parameters and roughness. Vocal characteristics of dysphonic children improve with age. Acknowledgments This study was financed in part by the Coordena¸c ~ ao de Aperfei¸c oamento de Pessoal de Nível Superior - Brasil (CAPES) Finance Code 001. C. A. Cielo acknowledges support from Brazilian agency CNPq (Grant 301326/2017-7). The authors thank Prof L S Dorneles (English revision). SUPPLEMENTARY MATERIALS Supplementary material associated with this article can be found in the online version at https://doi.org/10.1016/j. jvoice.2019.12.004. REFERENCES 1. Possamai V, Hartley B. Dysphonia in children. Ped Clinic. 2013;13:1–5. 2. Azevedo R. Disfonia na Inf^ancia. In: Fernandes FDM, Mendes BCA, Navas ALPGP, eds. Tratado de Fonoaudiologia. 2 Ed. S~ao Paulo: Roca; 2009. 3. Fritsch A, Oliveira G, Behlau M. Parents opinion on the voice and on behavior and personality characteristics of their children. Rev CEFAC. 2011;13:112–122. 4. Vanzella TP. Normatiza¸c ~ao dos par^ametros acusticos vocais em crian¸c as em idade escolar. 2006. S~ao Paulo: Disserta¸c ~ao (Mestrado em Bioengenharia), Universidade de S~ao Paulo; 2006. 5. Krohling LL, Pereira De Paula KM, Behlau MS. Behavior, social competence, and voice disorders in childhood and adolescence. J Voice. 2015; 30:677–683. 6. Lopes LW, Barbosa Lima IL, Alves Almeida LN, et al. Severity of voice disorders in children: correlations between perceptual and acoustic data. J Voice. 2012;26:807–812. 7. Nicollas R, Giovani A, Triglia JM. Dysphonia in children. Arch Pediatr Adolesc Med. 2008;15(6):1133–1138. 8. Oliveira RC, Teixeira LC, Gama ACC, et al. Auditory-perceptive, acoustic and vocal self-perception analyses in children. J Soc Bras Fonoaudiol. 2011;23:158–163. 9. Pribuisiene R, Uloza V, Kardisiene V. Voice characteristics of children aged between 6 and 13 years: impact of age, gender, and vocal training. Logoped Phoniatr Vocol. 2011;36:150–155. 10. Tavares ELM, Labio RB, Martins RHG. Normative study of vocal acoustic parameters from children from 4 to 12 years of age without
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Characteristics of the Voice of Dysphonic School Children
vocal symptoms. A pilot study. J Bras Otorrinolaringol.. 2010;76: 485–490. Weinrich B, Brehm SB, Knudsen C, et al. Pediatric normative data for KayPENTAX PAS Model 660. J Voice. 2013;27:46–56. Cappellari VM, Cielo CA. Vocal acoustic characteristics in pre-school aged children. Rev Bras Otorrinolaringol. 2008;74:265–272. Guzman M, Mu~ noz D, Vivero M, et al. Acoustic markers to differentiate gender in prepubescent children’s speaking and singing voice. Int J Pediatr Otorhinolaryngol. 2014;78(10):1592–1598. Maturo S, Hill C, Bunting G, et al. Establishment of a normative pediatric acoustic database. Arch Otolaryngol Head Neck Surg. 2012; 138:956–961. Tezcaner CZ, Karatayli Ozgursoy S, Sati I, et al. Changes after voice therapy in objective and subjective voice measurements of pediatric patients with vocal nodules. Eur Arch Otorhinolaryngol. 2009;266: 1923–1927. Brockmann-Bauser M, Beyer D, Bohlender KD. Reliable acoustic measurements in children between 5;0 and 9;11 years: gender, age, height and weight effects on fundamental frequency, jitter and shimmer in phonations without and with controlled voice SPL. Int J Pediatr Otorhinolaryngol. 2015;79:2035–2042. Connor NP, et al. Attitudes of children with dysphonia. J Voice. 2008;2:197–209. Kallvik E, Putus I, Simberg S. Indoor air problems and hoarseness in children. J Voice. 2016;30:109–113. Verduyckt I, Remacle M, Jamart J, et al. Voice-related complaints in the pediatric population. J Voice. 2011;25:373–380. Aires F, Fernandes K, Hoffmann CF, et al. Auditory-perceptual characteristics of the voice of nondysphonic school children from 8:0 to 10:0 years old. J Voice. 2019;33:946.e1–946.e5. Viegas D, Viegas F, Atherino CCT, et al. Par^ametros Espectrais da Voz em Crian¸c as Respiradoras Orais. Rev CEFAC. 2010;12:820–883. American Speech-Language-Hearing Association. Consensus auditory-perceptual evaluation of voice CAPE-V.
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23. Behlau M. Consensus auditory: perceptual evaluation of voice (CAPE-V), ASHA 2003. New reflexions. Rev Soc Bras Fonoaud. 2004;9:187–189. 24. Barsties B, Bodt M. Assessment of voice quality: Current state-of-theart. Auris Nasus Larynx. 2015;42:183–188. 25. Kelchner LN, et al. Perceptual evaluation of severe pediatric voice disorders: rater reliability using the consensus auditory perceptual evaluation of voice. J Voice. 2008;78:1–10. 26. Stepp CE, et al. Effects of voice therapy on relative fundamental frequency during voicing offset and onset in patients with vocal hyperfunction. J Speech Lang Hear Res. 2011;54:1260–1266. 27. Paes SM, Azevedo RR. Efeito do apoio visual nas medidas de tempo máximo fonat orio em crian¸c as. Rev Dist Comun. 2010;22:13–18. 28. Sampaio M, Oliveira G, Behlau M. Investigation of the immediate effects of two semi-ocluded vocal tract exercises. Pro-Fono. 2008;20:261–266. 29. Cortes MG, Gama ACC. Visual analysis of spectrographic parameters before and after dysphonia therapy. Rev Soc Bras Fonoaudiol. 2010;15:243–249. 30. Diercks G, et al. Consistency of voice frequency and perturbation measures in children using cepstral analyses - a movement toward increased recording stability. JAMA Otolaryngol Head Neck Surg. 2013;139:811–816. 31. Viegas F, Viegas D, Baek HE. Frequency measurement of vowel formants produced by brazilian children aged between 4 and 8 years. J Voice. 2015;29:292–298. 32. Braga JN, Oliveira DS, Sampaio TM. Fundamental frequency of children's voice. Rev CEFAC. 2009;12:234–240. 33. Valadez V, Ysunza A, Ocharan-Hernandez E, et al. Voice parameters and videonasolaryngoscopy in children with vocal nodules: a longitudinal study, before and after voice therapy. Intern J Ped Otorhinolaryngol. 2012;76:1361–1365. 34. Beber BC, Cielo CA. Vocal acoustic characteristic in men with normal voice and laryx. Rev CEFAC. 2011;13:340–351. 35. Ma EP, Yu CH. Listeners’ attitudes toward children with voice problems. J Speech Lang Hear Res. 2013;56:1409–1415.
Characteristics of the Voice of Dysphonic School Children from 4:0 to 7:11 Years Old Carla Franco Hoffmann, and Carla Aparecida Cielo, Santa Maria, Brazil Summary: Background. Childhood dysphonia is frequent and has many origins, with the most common initial symptom being the altered vocal quality. Objective. Describe and correlate the auditory-perceptual and acoustic characteristics of the voice, and the maximum phonation time (MPT), of dysphonic schoolchildren from private and public schools from 4:0 to 7:11 years old, female and male. Methods. MPT, acoustic (Multi-Dimensional Voice Program Advanced and Real Time Spectrogram), and auditory-perceptual (Consensus Auditory-Perceptual Evaluation of Voice) evaluations of 115 schoolchildren were statistically analyzed. Results. Auditory-perceptual parameters values were classified as mild, and MPT values were reduced, in most children. Fundamental frequency and Jitt values decreased significantly with age; MPT/i/ increased significantly with age. Relative average perturbation, voice turbulence index (VTI), and number of sub-harmonic segments values were significantly higher in 4:0 years old children. The number of unvoiced segments was higher in 6:0 years old children. Shimmer percent was higher in 7:0 years old children. There were negative correlations between the high frequency spectrographic tracing color intensity and the vocal strain; the VTI and the MPT; the degree of unvoiced segments and the MPT. There was a positive correlation between the smoothed pitch period perturbation quotient and the roughness. Conclusion. In dysphonic schoolchildren, auditory-perceptual parameters were moderate, MPT was reduced, several acoustic parameters were altered, and these vocal characteristics improved with age. Key Words: Larynx−voice−Voice quality−Child−Speech−Language and hearing sciences.
INTRODUCTION Childhood dysphonia is frequent and has many origins, with the most common initial symptom being the altered vocal quality. Parents or guardians may not detect this symptom, as they are used to the vocal characteristics of their children, so it may be detected first outside the family context.1 Children 4:0−7:11 years old may be identified as dysphonic for the first time by their teachers at school, outside of their home environment.1 Late detection of the abnormal vocal qualities may delay dysphonia identification and intervention, with consequences to the children. Even dysphonic children that are aware of their vocal limitation may not be able to express their frustration. In such cases, the voice can be used to express aggressiveness or to relieve stress by screaming, mainly while playing with other children.2−4 Also, introvert or repressed children, or the ones that find it difficult to socialize with other children, may have an increased muscular internal stress stored in the larynx and dysphonia.2,4 Childhood dysphonia may influence the perception of other children or adults. In a recent research, dysphonic children were described as “dirty,” “weak,” “sick,” or “ugly.”1 A survey analyzing parents of children and teenagers 6:0−18:0 years old showed that the group with vocal Accepted for publication December 2, 2019. From the Departamento de Fonoaudiologia, Universidade Federal de Santa Maria, Santa Maria, RS, Brazil. Address correspondence and reprint requests to Carla Aparecida Cielo, Departamento de Fonoaudiologia, Universidade Federal de Santa Maria, Santa Maria, RS 97105-900, Brazil. E-mail: [email protected] Journal of Voice, Vol. &&, No. &&, pp. &&−&& 0892-1997 © 2019 The Voice Foundation. Published by Elsevier Inc. All rights reserved. https://doi.org/10.1016/j.jvoice.2019.12.004
complaints presented risk of developing behavioral problems.5 Childhood dysphonia may also influence the choice of profession; children that lived negative experiences related to their voices may avoid working in professional classes that use the voice directly.2 Children’s voices presenting a mild degree of roughness or breathiness were considered nondysphonic.6−11 The maximum phonation time (MPT) value measured in seconds is equal to the age value measured in years for nondysphonic children,9−12 but in dysphonic children the MPT value is smaller than the age value.7 Also, in nondysphonic children the jitter, shimmer,7,13−15 and the fundamental frequency (F0)15,16 decrease with age. Some studies analyzed the voice, the social skills, the vocal habits, and the auditory processing of dysphonic and nondysphonic children.7,14,17 Other studies measured the prevalence of childhood dysphonia found to be within 6%−23%.8,10,18 Few studies described the vocal characteristics of dysphonic children6,19; this is the aim of our study. It is relevant to characterize the voice of dysphonic children. It is important to gather results from different vocal assessment procedures, and check how they correlate, so the diagnosis is more accurate, and the treatment is more effective. Our study aims at identifying and correlating the auditory-perceptual and acoustic vocal characteristics, and the vowels’ MPTs of dysphonic children 4:0−7:11 years old.
METHODS Ethical aspects The Research Ethics Committee of the authors’ institution approved this study (0306.0.243.000-10). All children orally
ARTICLE IN PRESS 2 stated their agreement to participate in the research, and their parents signed the Informed Consent, and all schools signed the Institutional Authorization Term. Research characteristics This is a contemporary, cross-sectional, analytical, quantitative study using data collected from students in public or private schools from a medium sized city with 280,505 inhabitants. Schools’ randomization A list containing the names of all the 104 schools in alphabetical order was constructed, and every third name was excluded in order to have a randomized list of schools; children from the excluded schools did not participate in this study. The Institutional Authorization Term was sent to the final list. Participants’ selection The parents answered the medical history interview regarding the anthropometric data, health history, and the development of the child. Afterwards, an auditory screening and a voice evaluation were performed in the child. Inclusion criterium was dysphonic child 4:0−7:11 years old. This criterium was chosen in order to exclude factors related to neuromuscular immaturity present in children less than 4:0 years old, or factors related to hormonal development that may be present in children more than 8:0 years old. Exclusion criteria were: report from the parents or guardians of delayed neuropsychomotor development, of psychological, psychiatric, postural, or pulmonary alterations, of syndromes; severe physical handicap or structural alterations that could compromise phonation at respiratory, phonatory, or articulatory levels; being under speech-language therapy for the voice at the time of data collection, or having done it previously to avoid interference of vocal training on vocal characteristics; surgery in orofacial region; influenza or respiratory allergies in the day of the evaluations.20 None of the participants had been previously evaluated for concerns of abnormal vocal qualities or have a known medical diagnosis related to their dysphonia. To exclude children with suspected hearing loss, an auditory screening was performed by a speech therapist21 within the 1−4 kHz frequency range at 20 dB, by air (audiometer Amplivox, model 2011, type A260), in a quiet environment with noise level (measured with Instrutherm model Dec-480) below 50 dBNPS (Res. 274/01−Brazilian Federal Council of Speech, Language and Hearing Sciences). For the classification of dysphonic voice (inclusion criterium) and nondysphonic voice, also by speech therapist,21 “equally spaced” version of Consensus Auditory-Perceptual Evaluation of Voice (CAPE-V)22 was used, adapted for Portuguese.23 Using sustained emissions, phrase repetitions, and spontaneous speech, the CAPE-V allows one to measure aspects of the
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vocal quality such as overall severity of dysphonia, roughness, breathiness, strain, pitch, loudness, and resonance. CAPE-V is composed of a linear analogue scale ranging from 0 to 100 mm, for each parameter. The parameters pitch, loudness, and resonance were not measured in this study. Those children who presented an overall severity greater than moderate (from 50%) were considered dysphonic. There could be numerous etiologies for the dysphonia described here, except those due to the exclusion criteria. Considering the children’s population of the city within the 4:0−7:11 age range (20,717), to obtain a 95% significance level, a sample of 237 children was necessary. A total of 1015 IC were distributed, and 427 were signed and returned authorizing the child’s participation in the study. One hundred ninety-two children were excluded for presenting normal voice or a mild level (up to 10%) of dysphonia; 97 children were excluded for being more than 7:11 years old; 15 children were excluded for having respiratory allergy in the day of the evaluations; 5 children were excluded for having pulmonary alteration; and 3 children were excluded for being reported with delayed neuropsychomotor development. The final sample was composed of 115 children, that were divided into four groups; group I: 19 children 4:0−4:11 years old; group II: 24 children 5:0−5:11 years old; group III: 33 children 6:0−6:11 years old; group IV: 39 children 7:0−7:11 years old. DATA COLLECTION Each child sustained MPT/a/, /i/, and /u/ after taking deep breath, in regular pitch, loudness, and vocal quality.12,20,24,25 The tongue is at a different position during the emission of each of these vowels (the vowel triangle), so differences in the vocal tract impedance may cause differences among MPTs. Three measurements of each MPT vowel were timed in seconds, and the longest time was considered.12,24,25 To sample the spontaneous speech, each child talked about what he/she liked to do during recess, and about his/her thoughts on his/ her own voice. Also, they repeated all CAPE-V phrases. All recordings were performed before recess and physical education classes to avoid interference from the intensive and/or abusive use of the voice, and at only one occasion. To record the vocal emissions, a professional digital recorder Zoom model H4n was used, 16 bit audio format pulse-code modulation, 96-kHz sampling frequency, Behringer ECM 8000 omnidirectional microphone with a flat band frequency range from 15 to 20 kHz, positioned horizontally in front of the child's mouth, at a fixed distance of 4 cm for the MPT recording, and at a fixed distance of 10 cm for the spontaneous speech and phrases. The recording sessions took place in a room with ambient noise of less than 50 dBNPS, measured using a digital sound pressure level meter model Dec-480.20 Three judges with more than 3 years of experience in voice evaluated, individually, the auditory-perceptual characteristics of the 115 children’s voices.20 The judges were instructed on the CAPE-V scale parameters and their
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Characteristics of the Voice of Dysphonic School Children
marking, considering parameters roughness, breathiness, strain, and overall severity of dysphonia.8,20,21,25 For the statistical calculations, the arithmetic mean of the evaluations of the judges in each of the CAPE-V protocol items was considered.8,20,24,25,26 In the acoustic vocal evaluation, the unstable initial and final portions of the emission of MPT/a/ were removed, so instabilities in the vocal signal are avoided and do not influence data analysis.8,24,27 The shortest MPT/a/ time among all subjects was 3 seconds, determined by the time window acoustic analysis.12,28 Detailed editing specifications are described below. In the acoustic analysis of the glottal signal, the Kay Pentax Multi-Dimensional Voice Program Advanced (MDVPA) was used with 44 kHz sampling rate and 16 bits analog-digital conversion. Each parameter analysis was based in several measurements: frequency measurements: fundamental frequency (f0), f0 high (fhi), f0 low (flo), standard deviation of f0 (STD); frequency perturbation measurements: absolute jitter (Jita), jitter percent (Jitt), relative average perturbation (RAP), pitch perturbation quotient (PPQ), smoothed pitch perturbation quotient (sPPQ), f0 variation (vf0); amplitude perturbation measurements: shimmer in dB (ShdB), shimmer percent (Shim), amplitude perturbation quotient (APQ), smoothed amplitude perturbation quotient (sAPQ), peak-topeak amplitude variation; noise measurements: noise to harmonic ratio, voice turbulence index (VTI), soft phonation index; voice break measurements: degree of voice breaks, number of voice breaks; unvoiced segments measurements: number of unvoiced segments (NUV), degree of unvoiced segments (DUV); sub-harmonic segments measurements: degree of sub-harmonic components, number of sub-harmonic segments. In the spectrographic voice acoustic analysis the Kay Pentax Real Time Spectrogram was used to generate broadband spectrogram (BBS) filtered in 100 points (646 Hz) and narrowband spectrogram (NBS) filtered with 1024 points (63.09 Hz), with 11 kHz sampling rate, 16 bits analog-digital conversion, and 5 kHz window. The spectrographic analysis was performed by four speech therapist judges (different from the judges who performed the CAPE-V evaluation) with more than three years of experience in voice acoustic analysis, using a specific protocol created by the authors (to be published). The judges received two standard normal voice spectrograms to guide their judgment, one BBS and one NBS.29 The judges also received the 115 subjects’ BBS and NBS of the vowel /a/ without the vocal auditory signal, to avoid its influence on the judgment.29 It was considered the predominant opinion among the judges for each item of the protocol. In exceptional cases where no agreement was obtained, a fifth judge was consulted. The judges were blinded to the objective of the study, age, and gender of the children; they are not authors of this study.27,29 In the BBS the following parameters were evaluated: tracing color intensity of the formants F (F1, F2, F3, and F4); tracing color intensity at high frequencies; tracing color
3
intensity in the entire vocal spectrogram; noise at high frequencies; noise in the entire vocal spectrogram; definition of F; regularity of the tracing. In the NBS, the following parameters were evaluated: tracing color intensity at high frequencies; tracing color intensity in the entire vocal spectrogram; noise between the harmonics at high frequencies; noise between the harmonics in the entire vocal spectrogram; replacement of harmonics by noise at high frequencies; replacement of harmonics by noise in the entire vocal spectrogram; definition of harmonics; regularity of the tracing; number of harmonics; presence of subharmonics. Data analysis We used the Kruskall-Wallis nonparametric test to compare age groups I, II, III, and IV. The correlations among the results from MPT, MDVPA, CAPE-V, BBS, and NBS, were tested using the Spearman correlation coefficient. The significance level of 5% was adopted in all tests. RESULTS The Spearman correlation coefficient showed significant negative correlation between: auditory-perceptual parameter strain and NBS tracing color intensity at high frequencies (r = 0.7); auditory-perceptual parameter strain and BBS tracing color intensity at high frequencies (r = 0.6); VTI and MPT/i/ (r = 0.8); DUV and MPT/a/ (r = 0.7); DUV and MPT/i/ (r = 0.6); DUV and MPT/u/ (r = 0.8). It showed significant positive correlation between the auditory-perceptual parameter roughness and sAPQ (r = 0.9). No other significant correlations were observed. DISCUSSION The MPT increased with age, with significance for MPT/i/. Group IV sustained vocal emission for longer (Table 1). According to references,10,27 the MPT in seconds is proportional to the children’s age in years; this fact can be attributed to the laryngeal anatomophysiological development and to the neurological maturation during childhood.9,10,12 When compared to other studies on children with normal voice,10,12 the MPT in our study is reduced, as expected for dysphonic children.7 A study with 60 children and teenagers with normal voice and ages within the 6:0−17:11 years age range, found that the group with ages from 6:0 to 9:11 years had MPT of 11.3 s for girls and of 12.5 s for boys.11 A study with 75 singer and nonsinger children and ages within the 6:0 to 13:0 years age range, found an average MPT of 15.9 s for nonsingers and of 15.4 s for singers, concluding that singing practice did not influence MPT.9 Regarding the auditory-perceptual analysis, some authors consider the presence of roughness and breathiness in the child’s voice as normal, and other authors consider it as a pathological sign depending on the degree.8 In our study we considered a mild degree (up to 10%) of roughness and breathiness as normal in the child’s voice,6,10 as these are the most common characteristics in children. Most dysphonic
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TABLE 1. Maximum Phonation Time Comparison Among Groups I−IV GI (4−4:11 yo)
DP
GII (5−5:11 yo)
DP
GIII (6−6:11 yo)
DP
GIV (7−7:11 yo)
DP
P Value
4.90 4.71 3.93
0.75 0.25 0.55
5.30 5.28 4.55
0.84 0.75 0.72
5.66 5.79 5.33
0.15 0.19 0.23
6.40 7.09 6.51
0.21 0.42 0.84
0.56 0.01* 0.08
TMF/a/ (s) TMF/i/ (s) TMF/u/ (s)
* Data statistically significant (P < 0.05). Kruskall-Wallis test. There was difference among the groups for MPT/i/. Abbreviations: G, group; SD, standard deviation; yo, years old; MPT, maximum phonation time.
children in our study, of all ages, presented moderate degree of overall severity and of all the other vocal parameters (roughness, breathiness, and strain), with statistical significance and showing the presence of dysphonia (Table 2). A study Kallvik et al with 217 children within the 6:0−10:0 years age range questioned parents and teachers on the children’s vocal quality and correlated this data with the CAPE-V data, founding roughness as the most frequent vocal characteristic.18 A study from Diercks et al concluded that auditory-perceptual vocal evaluation is a reliable method, as the results were the same for measurements made at two different times.30 Another study from Tezcaner et al found that the auditory-perceptual vocal evaluation is a reliable method to follow the vocal changes during therapy of dysphonic children within the 7:0−14:0 years age range.15 F0 e Jitt decreased significantly with age. RAP, VTI, and number of sub-harmonic segments were significantly higher for children 4:0 years old, NUV was significantly higher for children 6:0 years old, and Shim was significantly higher for children 7:0 years old (Table 3). F0 values for groups I−IV were 268.1 Hz, 255.0 Hz, 253.1 Hz, and 241.3 Hz, respectively (Table 3); F0 is expected to decrease with age, due to body growth.31 In our study we found F0 values lower in dysphonic children than the ones found in studies with nondysphonic children.10,21,32 This may suggest the existence of increased vocal folds’
mass due to edema or vocal nodule, a common laryngeal pathology in children within the studied age range.7,21,29 In a study from Tavares et al with boys and girls aged 4:0−7:0 years, F0 for girls within the 4:0−5:0 years age range was 275 Hz, and for boys and girls within the 6:0−7:0 years age range they were 243.37 Hz and 258.03 Hz, respectively.10. In a study from Braga et al with nondysphonic children, F0 was 263.65 Hz for children 6:0 years old, and 250.55 Hz for children 7:0 years old.32 In a study from Viegas et al with children within the 6:0−7:0 years age range, F0 was 258 Hz.21 In another study from Brockmann-Bauser et al with 68 nondysphonic children within the 5:0−9:11 years age range, F0 was 276 Hz for girls and 261 Hz for boys.16 In a study from Nicollas et al with 212 nondysphonic children within the 6:0−9:0 years age range, F0 decreased with age; jitter and shimmer also decreased with age, but not with statistical significance.7 This behavior was also found in our study where F0 and Jitt significantly decreased with age. Another study from Maturo et al with 336 nondysphonic children found that both boys and girls within the 4:0−12:0 years age range had the same vocal profile; F0 was 279 Hz and shimmer and jitter values were similar to the values found in adults.14 A study from Valadez et al with 20 children with vocal nodules found significantly different acoustic vocal
TABLE 2. CAPE-V Comparison Among Groups I−IV Parameter Overall severity Roughness Breathiness Strain
M S M S M S M S
G I (4−4:11 yo) (n)
(%)
GII (5−5:11 yo) (n)
(%)
GIII (6−6:11 yo) (n)
(%)
GIV (7−7:11 yo) (n)
(%)
P Value
16 3 15 4 19 0 19 0
84.21 15.78 78.94 21.05 100 0 100 0
21 3 22 2 24 0 24 0
87.5 12.5 91.66 8.33 100 0 100 0
30 3 29 4 30 3 33 0
90.09 9.9 87.98 12.12 90.9 9.09 100 0
34 5 37 2 39 0 39 0
89.75 12.82 94.87 5.12 100 0 100 0
0.89
Kruskall-Wallis test. The data in this table are not statistically significant. Abbreviations: G, group; SD, standard deviation; yo, years old; n, number of subjects; %, percentage of subjects; M, moderate; S, severe.
0.31 0.28 0.49
Frequency measurements Frequency perturbation measurements
Voice breaks measurements Unvoiced segments measurements Sub-harmonic segments measurements
DP
GII (5−5:11 yo)
DP
GIII (6−6:11 yo)
DP
GIV (7−7:11 yo)
DP
P Value
268.1 11.5 66.7 2.4 1.7 1.8 3.8 5.3 1.3 6.2 4.4 5.9 19.3 0.2 0.1 3.3 1.5 5.8 3.0 9.5 5.6 5.1
0.15 0.16 0.15 0.23 0.22 0.17 0.33 0.24 0.15 0.15 0.17 0.18 0.22 0.17 0.26 0.27 0.23 0.27 0.28 0.25 0.15 0.16
255.0 14.2 115.3 1.9 1.1 1.2 1.0 6.1 0.8 5.3 4.3 4.8 15.7 0.2 0.1 ; 0.1 2.7 2.7 3.8 2.6 3.1
0.25 0.17 0.18 0.21 0.26 0.24 0.16 0.19 0.18 0.22 0.25 0.15 0.17 0.29 0.24 ; 0.15 0.17 0.18 0.15 0.18 0.19
253.1 9.4 72.4 1.8 1.1 1.1 1.2 3.4 0.5 6.1 4.3 6.2 19.2 0.2 0.6 4.7 0.0 3.2 3.7 0.5 4.2 4.1
0.24 0.16 0.18 0.22 0.25 0.27 0.25 0.15 0.23 0.16 0.15 0.17 0.26 0.18 0.25 0.21 0.18 0.15 0.23 0.25 0.15 0.19
241.3 17.5 90.0 1.2 1.3 1.4 2.5 6.8 0.6 7.2 5.1 6.7 20.9 0.2 0.5 3.8 0.4 5.7 1.1 2.1 3.0 2.8
0.25 0.24 0.21 0.15 0.17 0.18 0.15 0.17 0.21 0.17 0.15 0.25 0.27 0.22 0.15 \ 0.21 0.16 0.15 0.24 0.21 0.28
0.01* 0.17 0.85 0.03* 0.03* 0.45 0.71 0.41 0.22 0.02* 0.75 0.64 0.06 0.05 0.02* 0.95 0.37 0.68 0.03* 0.52 0.07 0.04*
* Data statistically significant (P < 0.05). Kruskall-Wallis test. Abbreviations: G, group; SD, standard deviation; yo, years old; %, percentage; f0, fundamental frequency; fhi, f0 high; flo, f0 low; STD, standard deviation of f0; Jita, absolute jitter; Jitt, jitter percent; RAP, relative average perturbation; PPQ, pitch perturbation quotient; sPPQ, smoothed pitch perturbation quotient; vf0, f0 variation; ShdB, shimmer in dB; Shim, shimmer percent; APQ, amplitude perturbation quotient; sAPQ, smoothed amplitude perturbation quotient; vAm, peak-to-peak amplitude variation; NHR, noise to harmonic ratio; VTI, voice turbulence index; SPI, soft phonation index; DVB, degree of voice breaks; NVB, number of voice breaks; NUV, number of unvoiced segments; DUV, degree of unvoiced segments; DSH, degree of sub-harmonic components; NSH, number of sub-harmonic segments.
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Noise measurements
GI (4−4:11 yo)
Characteristics of the Voice of Dysphonic School Children
Amplitude perturbation measurements
F0 (Hz) STD (Hz) Jita (us) Jitt (%) RAP (%) PPQ (%) sPPQ (%) vF0 (%) Shdb (dB) Shim (%) APQ (%) sAPQ (%) vAm (%) NHR VTI SPI DVB (%) NVB (%) NUV (%) DUV (%) DSH (%) NSH (%)
Carla Franco Hoffmann and Carla Aparecida Cielo
TABLE 3. Multi-Dimensional Voice Program Advanced Comparison Among Groups I−IV
5
ARTICLE IN PRESS 6
Journal of Voice, Vol. &&, No. &&, 2019
TABLE 4. Broadband Spectrograms Comparison Among Groups I to IV Parameters Tracing color intensity F1
Weak Medium Strong Tracing color Weak intensity F2 Medium Strong Tracing color Weak intensity F3 Medium Strong Tracing color Weak intensity F4 Medium Strong Tracing color intensity Weak at high frequencies Medium Strong Tracing color intensity Weak in the entire Medium spectrogram Strong Noise in the entire Absent spectrogram Barely present Present Noise at high Absent frequencies Barely present Present Definition of F1 Absent Barely defined Defined Definition of F2 Absent Barely defined Defined Definition of F3 Absent Barely defined Defined Definition of F4 Absent Barely defined Defined Regularity of Low the tracing Medium High
GI (4−4:11 GII (5−5:11 GIII (6−6:11 GIV (7−7:11 yo) (n) (%) yo) (n) (%) yo) (n) (%) yo) (n) (%) P Value 2 8 9 4 10 5 10 5 4 12 2 5 8 9 2 5 0 14 0 1 18 0 1 18 4 6 9 8 7 4 16 3 0 15 4 0 13 6 0
11 42 47 21 53 26 53 26 21 63 11 26 42 47 11 26 0 74 0 5 95 0 5 95 21 32 47 42 37 21 84 16 0 79 21 0 69 31 0
0 15 9 3 13 8 15 5 4 20 2 2 11 7 6 14 3 7 19 5 0 0 5 19 7 11 6 12 9 3 16 8 0 22 2 0 15 9 0
0 62 38 13 54 33 62 21 17 84 8 8 46 29 25 58 13 29 79 21 0 0 21 79 29 46 25 50 38 12 67 33 0 92 8 0 63 37 0
9 15 9 14 5 14 27 1 4 25 2 6 14 13 6 0 8 25 0 8 25 31 2 0 8 20 5 18 12 3 27 6 0 31 2 0 22 11 0
27 46 27 42 16 42 84 3 13 76 6 18 43 39 18 0 24 76 0 24 76 94 6 0 24 61 15 55 36 9 81 19 94 6 0 67 33 0
7 17 15 0 30 9 24 10 5 16 22 1 7 25 7 12 14 13 2 9 28 32 7 0 9 20 10 18 6 15 32 7 0 35 4 0 20 19 0
18 44 38 0 77 23 61 26 13 41 56 3 18 64 18 31 36 33 5 23 72 82 18 0 23 51 26 47 15 38 82 18 0 90 10 0 51 49 0
0.89
0.56
0.25
0.1
0.76
0.33
0.12
0.15
0.35
0.21
0.1
0.35
0.15
Kruskall-Wallis test. The data in this table are not statistically significant. Abbreviations: G, group; SD, standard deviation; yo, years old; n, number of subjects; %, percentage of subjects; F, formant.
parameters when comparing to nondysphonic children, for example decreased values of F0 and increased values of shimmer and jitter,33 in accordance with our study. In another study from Tezcaner et al with dysphonic children within the 7:0−14:0 years age range, before voice therapy F0 was 275 Hz, Jitt was 2.51%, and Shim was 6.39%; and after voice therapy all values decreased.15 In our study, Shim was higher for children 7:0 years old (Table 3), in disagreement with studies with nondysphonic children.7,10 This measurement is related to the vocal amplitude variation periodicity, that may be related to the presence
of noise in the emission, mainly breathiness. This finding, due to its significance, characterized 7:0 years old dysphonic children in our study. In a study from Brockmann-Bauser et al with average 7:6 years old nondysphonic children Shim was 9.5%, higher than in our study, and Jitt was 0.5%.16 In another study from Guzman et al with average 8:10 years old nondysphonic children, within the 7:0−10:0 years age range, average shimmer was 8.04% for boys and 7.12% for girls, and jitter was 0.56% for boys and 0.48% for girls.13 In both studies jitter values were lower than the values found in our
Tracing color intensity in the entire vocal spectrogram
Noise between the harmonics in the entire spectrogram Definition of harmonics
Regularity of the tracing
GII (5−5:11 yo)
(%)
GIII (6−6:11 yo)
(%)
GV (7−7:11 yo)
(%)
P Value
15 4 0 15 4 0 12 3 4 18 1 0 13 6 0 12 4 3
79 21 0 79 21 0 63 16 21 95 5 0 68 32 0 63 21 16
20 4 0 19 5 0 15 5 4 18 3 3 22 2 0 12 8 4
83 17 0 79 21 0 62 21 17 76 13 13 92 8 0 50 33 17
17 13 3 25 8 0 21 10 2 13 15 5 21 10 2 33 0 0
52 39 9 76 24 0 64 30 6 39 46 15 64 30 6 100 0 0
30 9 0 25 10 4 21 12 6 17 13 9 29 10 0 21 15 3
77 23 0 64 26 10 54 31 15 44 33 23 74 26 0 54 38 8
0.87
Kruskall-Wallis test. The data in this table are not statistically significant. Abbreviations: G, group; SD, standard deviation; y, years; n, number of subjects; %, percentage of subjects.
0.96
0.67
0.89
0.08
0.07
Characteristics of the Voice of Dysphonic School Children
Noise between the harmonics at high frequencies
Weak Medium Strong Weak Medium Strong Absent Barely present Present Absent Barely present Present Absent Barely present Present Low Medium High
(%)
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Tracing color intensity at high frequencies
GI (4−4:11 yo)
Carla Franco Hoffmann and Carla Aparecida Cielo
TABLE 5. Narrowband Spectrograms Comparison Among Groups I−IV
7
ARTICLE IN PRESS 8 study with dysphonic children. In children 6:0 years old, NUV value was higher, suggesting the presence of noise in the emission. To verify this behavior, we suggest a study using a larger sample size, as it is observed a peak in the occurrence of vocal nodules within this age range, a common pathology in schoolchildren.1,2,31,33 The spectrographic voice acoustic data had no statistically significant differences among age groups. For BBS in most children, trancing color intensity of F and at high frequencies was weak or medium; noise in the entire vocal spectrogram was present; noise at high frequencies was present; definition of F was barely present or absent; and regularity of the tracing was low or medium (Table 4). For NBS in most children, tracing color intensity at high frequencies and in the entire vocal spectrogram was weak; noise between the harmonics at high frequencies and in the entire spectrogram was absent; definition of harmonics was absent; and regularity of the tracing was low (Table 5). These findings corroborate the auditoryperceptual findings of dysphonia with roughness, breathiness, and strain in a moderate degree. There was negative correlation between tracing color intensity at high frequencies (from both BBS and NBS) and the auditory-perceptual parameter strain. As the tracing color intensity is related to the sound pressure level and to the voice projection, the vocal productions with strain had low harmonic energy at high frequencies and weak vocal projection.29. The higher the VTI (noise in the vocal production), the shorter the MPT/i/; the higher the DUV (interruption in the sound wave, resulting in irregularity or noise in the vocal production), the shorter the MPT/a,i,u/. Acoustic measurements reflect the vocal behavior at the glottal level, while MPT measurements reflect the relation between the muscular and muco-undulatory action of the vocal folds, and the air flow from the lungs.31,33 Our results show that the presence of acoustic noise, common in dysphonic children, is related to the shortening of the MPT.7,10 There was positive correlation between sAPQ and roughness (caused by the aperiodic vibration of the vocal folds). Measurements of amplitude perturbation or shimmer, as sAPQ, indicate the periodicity of the vocal folds’ vibration cycles. Consequently, the values of sAPQ indicate their degree of stability and amount of harmonic energy. According to the study from Beber et al, an increase in the value of the shimmer parameter suggests acoustic noise in the vocal production, characterized by roughness, breathiness, or hoarseness.34 A study from Lopes et al evaluated 71 children within the 3:0−9:0 years age range and found a mild level of the auditory-perceptual vocal characteristics strain, instability, and breathiness, and positive correlation between F0 and strain, and between roughness and instability.6 These results are similar to the results found in our study. According to the study from Ma et al, the mean attitude ratings received by 6 children with dysphonic voice were significantly lower (ie, less favorable) than those received by
Journal of Voice, Vol. &&, No. &&, 2019
children with healthy voices. This indicates that the results from our study may be also important to help dysphonic children fight against social stigma.35 The results from our study on the characteristics of the voice of dysphonic children may help early screening and identification of childhood dysphonia, and intervention. It will avoid the harmful consequences of dysphonia1,2,5 in child development. CONCLUSION Dysphonic children presented moderate degree alterations in auditory-perceptual parameters, and reduced MPT. Fundamental frequency decreased with age and was lower than nondysphonic children’s fundamental frequency. Acoustic alterations were more present in 4:0-year-old children. The spectrographic tracing color intensity at high frequencies decreased with vocal strain; MPT decreased with the increase in the presence of some noise parameters and roughness. Vocal characteristics of dysphonic children improve with age. Acknowledgments This study was financed in part by the Coordena¸c ~ ao de Aperfei¸c oamento de Pessoal de Nível Superior - Brasil (CAPES) Finance Code 001. C. A. Cielo acknowledges support from Brazilian agency CNPq (Grant 301326/2017-7). The authors thank Prof L S Dorneles (English revision). SUPPLEMENTARY MATERIALS Supplementary material associated with this article can be found in the online version at https://doi.org/10.1016/j. jvoice.2019.12.004. REFERENCES 1. Possamai V, Hartley B. Dysphonia in children. Ped Clinic. 2013;13:1–5. 2. Azevedo R. Disfonia na Inf^ancia. In: Fernandes FDM, Mendes BCA, Navas ALPGP, eds. Tratado de Fonoaudiologia. 2 Ed. S~ao Paulo: Roca; 2009. 3. Fritsch A, Oliveira G, Behlau M. Parents opinion on the voice and on behavior and personality characteristics of their children. Rev CEFAC. 2011;13:112–122. 4. Vanzella TP. Normatiza¸c ~ao dos par^ametros acusticos vocais em crian¸c as em idade escolar. 2006. S~ao Paulo: Disserta¸c ~ao (Mestrado em Bioengenharia), Universidade de S~ao Paulo; 2006. 5. Krohling LL, Pereira De Paula KM, Behlau MS. Behavior, social competence, and voice disorders in childhood and adolescence. J Voice. 2015; 30:677–683. 6. Lopes LW, Barbosa Lima IL, Alves Almeida LN, et al. Severity of voice disorders in children: correlations between perceptual and acoustic data. J Voice. 2012;26:807–812. 7. Nicollas R, Giovani A, Triglia JM. Dysphonia in children. Arch Pediatr Adolesc Med. 2008;15(6):1133–1138. 8. Oliveira RC, Teixeira LC, Gama ACC, et al. Auditory-perceptive, acoustic and vocal self-perception analyses in children. J Soc Bras Fonoaudiol. 2011;23:158–163. 9. Pribuisiene R, Uloza V, Kardisiene V. Voice characteristics of children aged between 6 and 13 years: impact of age, gender, and vocal training. Logoped Phoniatr Vocol. 2011;36:150–155. 10. Tavares ELM, Labio RB, Martins RHG. Normative study of vocal acoustic parameters from children from 4 to 12 years of age without
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