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Ambulatory phonation monitoring in a sample of 92 call center operators
Giovanna Cantarella1, Elisabetta Iofrida1, Paola Boria2
1Otolaryngology Department, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy.
Objectives:
The voice is a primary work tool for call center operators, but the main risk factors for voice disorders in this category have not yet been clarified. This study aimed to analyze the vocal behavior in call center operators and search for correlations between the daily voice dose and the self-perceived voice-related handicap.
Study Design:
Prospective.
Subjects And Methods:
Ninety-two call center operators (aged 24-50 years) underwent ambulatory phonation monitoring during a working day and were administered the Voice Handicap Index (VHI) questionnaire and a questionnaire concerning smoking habits, symptoms, and extrawork activities requiring intensive voice use.
Results:
Mean percentage phonation time (PT) during work was 14.74% and ranged from 4% to 31%. There was a significant difference between the percentage PT in working time and in extrawork time; however, subjects with high percentage PT in working time maintained a high value also in extrawork time. The mean PT was 87.5 ± 35.8 minutes and was not correlated with age, gender, number of work hours, symptoms, extraprofessional voice use, and VHI scores. The mean amplitude was significantly higher in subjects with longer PT and higher pitch (P < 0.001). VHI score (median = 9) was slightly higher than in the general population but not related to the number of work hours, indicating that work time was not a critical factor in causing the perception of voice problems.
Conclusion:
Our study provides data about the voice behavior of a large cohort of call center operators and demonstrates that the number of work hours and the percentage PT are not statistically related to the perception of voice disturbances in this working category.
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