Teachers' and Children's Experiences after an Acoustic Intervention and a Noise-Controlling Workshop in Two Elementary Classrooms.

INTRODUCTION: Treating sources of noise is a novel aspect of voice ergonomics intended to enhance the preconditions for good voice production and easy listening. OBJECTIVE: To improve experiences of listening and voice ergonomics in classrooms. METHODS: Participants were two female elementary school teachers with voice symptoms and their pupils (n = 50). Two interventions were performed: the acoustic intervention and then the workshop intervention where the teachers and pupils were active. Teachers' voice symptoms and pupils' and teachers' experiences of the interventions were elicited by questionnaire. RESULTS: The teacher with many voice symptoms experienced more annoyance from sounds and benefitted more from the interventions. After the interventions both teachers suffered fewer voice breaks and voice symptoms such as lump and mucus in the throat. The pupils reported improvement in the teachers' voice clarity and audibility (p = 0.001). Pupils aged 12-13 years were more annoyed by sounds than those aged 8-9 years (p = 0.003). The older pupils experienced less sound annoyance after both interventions and the younger ones after the workshop intervention. CONCLUSIONS: The importance of good acoustics and individuals' ability to improve voice ergonomics and listening conditions was demonstrated.

Relationship between Activity Noise, Voice Parameters, and Voice Symptoms among Female Teachers.

OBJECTIVE: Our interest was in how teachers' voices behave during the delivery of lessons in core subjects (e.g., mathematics, science, etc.). We sought to evaluate the relationship between voice sound pressure level (SPL), vocal fundamental frequency (F0), voice symptoms, activity noise, and differences therein during the first and the last lessons in core subjects of the day. PATIENTS AND METHODS: The participants were 24 female elementary school teachers. Voice symptoms were evaluated by questionnaire. The data were recorded on 2 portable voice accumulators (VoxLog) from the first and last lessons of the day. The versions of accumulators differed by frequency weighting; therefore, the analysis and the results of noise and voice SPL were treated separately: unweighted (group 1) and A-weighted (group 2). RESULTS: Difference in voice SPL followed difference in activity noise. F0 increased between the first and last lessons. Correlations were found between differences in the noise and the voice symptoms of tiredness and dryness. Irritating mucus was associated with high F0 during the first lesson. CONCLUSION: An apparent increase in voice loading due to the activity noise was observed during lessons in core subjects. Collaboration between specialists in voice and acoustics and teachers and pupils is needed to reduce this voice loading.

Acoustic Voice Quality Index as a Potential Tool for Voice Screening.

INTRODUCTION: To diminish the risk of voice disorders in people who are highly dependent on their voices, such as teachers, vocal screening is important already at the beginning of such individuals' professional studies. A reliable, specified screening tool is needed. The Acoustic Voice Quality Index (AVQI) has been found to differentiate normal voices from abnormal voices and to serve as a treatment outcome measure. This study investigated whether AVQI could be a screening tool in combination with auditory- and self-perception of the voice to discriminate normal from slightly poor voices. TYPE OF STUDY: Experimental. METHODS: Some 128 female teaching students (mean age 26.39 years, SD 9.80 years) with no diagnosed voice disorders participated in this study. They read aloud a text in Finnish, sustained the vowel /a:/, and filled the Voice Handicap Index (VHI) questionnaire. Voice samples were recorded with an AKG C544L headset microphone, iFocusrite soundcard, and Praat software using a 44100 sample rate and 16-bit amplitude quantization. Five expert voice therapists evaluated the samples to determine the grade of dysphonia (G) using a scale of 0-0.5 (=normal), 0.5-1 (=mild), 1-2 (=moderate), and 2-3 (=severe). Three medial seconds of [a:] and the first 31 syllables of the text were analyzed using AVQI script version 03.01 in Praat (5.3.55). The analysis gives one AVQI score per participant (scale 0-10). The AVQI threshold of normal and disordered voices for Finnish speakers is 1.83; a Gmean = 0.0-0.5 and VHI score <19 were considered normal. Statistical analysis was done using the receiver operating characteristic (ROC) curve, Spearman's correlation coefficient, and the independent samples t test. RESULTS: According to the AVQI results, the area under the curve (AROC) was 0.554, which is fair. The Youden index gave a cutoff value of 0.30 with a sensitivity of 85% and a specificity of 81.1%. There were weak but significant correlations between Gmean and AVQI and two AVQI parameters, smoothed cepstral peak prominence and harmonic-to-noise ratio (r = 0.27; --0.24; -0.20, respectively; |P < 0.05); and between total VHI and AVQI score and cepstral peak prominence (r = 0.21; 0.20, respectively; P < 0.05). Furthermore, the AVQI scores differed significantly between the groups with a VHI total score <19 and ≥19. CONCLUSIONS: AVQI did not differentiate between voices that had been perceptually judged as normal or slightly abnormal, but a combination of perceptual assessment in the form of AVQI and VHI could better screen slightly deviant voices.