Prevalence of Voice Problems, Self-Reported Vocal Symptoms and Associated Risk Factors in Call Center Operators (CCOs): A Systematic Review



      The purpose of this study was to systematically review the available literature on the prevalence, self-reported voice symptoms, and associated risk factors for the development of voice problems in call center operators (CCO).

      Study Design

      a systematic review


      An electronic search from five databases based on the guidance of preferred reporting of items for systematic reviews and meta-analysis (PRISMA) yielded 15 articles that reported the different aspects of voice problems in CCOs. The methodological quality of the studies was analyzed using the National Institute of Health (NIH) questionnaire.


      The career prevalence of voice problems in CCOs varied from 33% to 68%, whereas point prevalence was at 27%. Hoarse/rough voice was the most prominent symptom reported by most of the studies. Vocal fatigue, effortful voice, and breaks/cracks in voice were the other reported vocal symptoms. Long working hours, short breaks between calls, noisy working environment, dry work environment, work stress, stressful calls, limited breaks, prolonged use of voice, insufficient vocal rest, throat clearing, and more caffeinated beverage intake were different risk factors having significant association with telemarketers reporting vocal symptoms.


      The present study results suggest that CCOs are at higher risk of developing voice problems. Further, the different vocal symptoms reported by CCOs are suggestive of vocal fatigue. In addition, multiple risk factors may be associated with the development of voice problems. However, the available literature is limited, and further studies with a larger sample size are required to corroborate the current findings.

      Key Words

      To read this article in full you will need to make a payment

      Purchase one-time access:

      Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online access
      One-time access price info
      • For academic or personal research use, select 'Academic and Personal'
      • For corporate R&D use, select 'Corporate R&D Professionals'


      Subscribe to Journal of Voice
      Already a print subscriber? Claim online access
      Already an online subscriber? Sign in
      Institutional Access: Sign in to ScienceDirect


        • Sprigg C
        • Smith P
        • Jackson P
        Psychosocial risk factors in call centres: an evaluation of work design and well-being.
        Health Safety Exec. 2003; 169
        • Jones K
        • Sigmon J
        • Hock L
        • et al.
        Prevalence and risk factors for voice problems among telemarketers.
        Arch Otolaryngol - Head Neck Surg. 2002; 128 ([Internet]May [cited 2021 May 21]Available from): 571-577
        • Lehto L
        • Rantala L
        • Vilkman E
        • et al.
        Experiences of a short vocal training course for call-centre customer service advisors.
        Folia Phoniatr Logop. 2003; 55: 163-176
      1. Batt R, Doellgast V, Kwon H, et al. The indian call centre industry: national benchmarking report strategy, HR practices, & performance. 2005 Jul.

        • Koufman JA
        • Isaacson G
        The spectrum of vocal dysfunction.
        Otolaryngol Clin North Am. 1991; 24 ([Internet]Oct 1 [cited 2021 May 21]Available from): 985-988
        • Devadas U
        • Rajashekhar B
        The prevalence and impact of voice problems in call center operators.
        J Laryngol Voice. 2013; 3: 3
        • Simberg S
        • Laine A
        • Sala E
        • et al.
        Prevalence of voice disorders among future teachers.
        J Voice. 2000; 14: 231-235
        • Roy N
        • Bless DM
        Personality traits and psychological factors in voice pathology: a foundation for future research.
        J Speech, Lang Hear Res. 2000; 43: 737-748
        • Schneider-Stickler B
        • Knell C
        • Aichstill B
        • et al.
        Biofeedback on voice use in call center agents in order to prevent occupational voice disorders.
        J Voice [Internet]. 2012; 26 (Available from): 51-62
        • Dassie-Leite AP
        • Lourenço L
        • Behlau M
        Relação entre dados ocupacionais, sintomas e avaliação vocal de operadores de telesserviços.
        Rev da Soc Bras Fonoaudiol. 2011; 16 (Mar): 59-63
        • Dos Santos CT
        • Santos C
        • Lopes LW
        • et al.
        Relationship between working and voice conditions self-reported by telemarketers of an emergency call center.
        CoDAS [Internet]. 2016; 28 (Available from): 583-594
        • Rechenberg L
        • Goulart B.N.
        • Roithmann R.
        Impact of call center work in subjective voice symptoms and complaints–an analytic study.
        Jornal da Sociedade Brasileira de Fonoaudiologia. 2011; 23: 301-307
        • Cameron D
        Styling the worker: gender and the commodification of language in the globalized service economy.
        J Socioling. 2000; 4 (Aug): 323-347
        • Hultgren Anna Kristina
        Talking like a man in a service job: Language, gender and stereotypes.
        in: 2nd Postgraduate Conference in Language Research, 19 Mar 2004, Cambridge, UK. 2004
        • Lehto L
        • Alku P
        • Bäckström T
        • et al.
        Voice symptoms of call-centre customer service advisers experienced during a work-day and effects of a short vocal training course.
        Logop Phoniatr Vocology. 2005; 30 ([Internet]Available from): 14-27
      2. Cochrane Handbook for Systematic Reviews of Interventions version 6.2 (updated February 2021). 2021; (editors) (Available from)
        • Page MJ
        • McKenzie JE
        • Bossuyt PM
        • et al.
        The PRISMA 2020 statement: An updated guideline for reporting systematic reviews.
        The BMJ. BMJ Publishing Group, 2021: 372 ([Internet][cited 2021 Jun 26]Available from)
        • Ouzzani M
        • Hammady H
        • Fedorowicz Z
        • et al.
        Rayyan-a web and mobile app for systematic reviews.
        Syst Rev. 2016 Dec 5; 5 ([Internet][cited 2020 Nov 28]Available from): 210
        • Oxman AD
        Grading quality of evidence and strength of recommendations. 328. British Medical Journal. BMJ Publishing Group, 2004: 1490-1494
      3. National heart Lung and blood Institute. Study Quality Assessment Tools | NHLBI, NIH.

        • Mathew A
        • Doorenbos AZ
        • Li H
        • et al.
        Allostatic load in cancer: a systematic review and mini meta-analysis.
        Biol Res Nurs. 2020;
        • Kim S
        • Savage TA
        • Hershberger PE
        • et al.
        End-of-life care in neonatal intensive care units from an asian perspective: an integrative review of the research literature.
        J Palliat Med. 2019; 22 (Mary Ann Liebert Inc.): 848-857
        • Oliveira AGA
        • Behlau M
        • Gouveia N
        Vocal symptoms in telemarketers: a random and controlled field trial.
        Folia Phoniatr Logop. 2009; 61: 76-82
        • Cantarella G.
        • Iofrida E.
        • Boria P.
        • et al.
        Ambulatory phonation monitoring in a sample of 92 call center operators.
        J Voice. 2014; 28: 393.e1-393.e3936
        • Fuentes-López E.
        • Fuente A.
        • Contreras K.V.
        Inadequate vocal hygiene habits associated with the presence of self-reported voice symptoms in telemarketers.
        Logoped Phoniatr Vocol. 2019; 44: 105-114
        • dos Santos AP
        • Silverio KCA
        • Dassie-Leite AP
        • et al.
        Relation between musculoskeletal pain and voice self-assessment in tele-operators.
        J Voice. 2019; 33 ([Internet]NovAvailable from): 948.e11-948.e21
        • Amorim G.O.
        • Bommarito S.
        • Kanashiro C.A.
        • et al.
        Comportamento vocal de teleoperadores pré e pós-jornada de trabalho [The vocal behavior of telemarketing operators before and after a working day].
        Jornal da Sociedade Brasileira de Fonoaudiologia. 2011; 23: 170-176
        • Ben-David BM
        • Icht M.
        Voice changes in real speaking situations during a day, with and without vocal loading: assessing call center operators.
        J Voice. 2016; 30 ([Internet]MarAvailable from): 247.e1-247.e11
        • Piwowarczyk T.C.
        • Oliveira G.
        • Lourenço L.
        • et al.
        Vocal symptoms, voice activity, and participation profile and professional performance of call center operators.
        J Voice. 2012; 26: 194-200
        • Devadas U
        • B. R
        • Rajashekhar B
        Acoustic and auditory perceptual characteristics of voice in Call Center Operators.
        J All India Inst Speech Hear. 2014; 33 ([Internet]Available from): 24-32
        • Coşkun Beyan A.
        • Dirican A.
        • Özkaya Ş.
        • et al.
        The cough frequency among call center workers: "call center cough". Çağrı merkezi çalışanlarında öksürük yakınma sıklığı: "çağrı merkezi öksürüğü".
        Tuberkuloz ve toraks. 2017; 65: 296-300
        • Boone DR
        • McFarlane SC.
        The Voice and Voice Therapy.
        Presntice-Hall, Englewood Cliffs, NJ1988
        • Colton R.H.
        • Casper J.K.
        • Leonard R.J.
        Understanding voice problem: a physiological perspective for diagnosis and treatment: Fourth edition.
        Wolters Kluwer Health Adis (ESP). 2011;
        • Tavares E.L.
        • Martins R.H.
        Vocal evaluation in teachers with or without symptoms.
        J Voice. 2007; 21: 407-414
        • Hemler RJB
        • Wieneke GH
        • Dejonckere PH.
        The effect of relative humidity of inhaled air on acoustic parameters of voice in normal subjects.
        J Voice. 1997; 11: 295-300
        • Chan RW
        • Tayama N.
        Biomechanical effects of hydration in vocal fold tissues.
        Otolaryngol - Head Neck Surg. 2002; 126 ([Internet]May 1 [cited 2021 Jan 7]Available from): 528-537
        • Verdolini K
        • Min Y
        • Titze IR
        • et al.
        Biological mechanisms underlying voice changes due to dehydration.
        J Speech, Lang Hear Res. 2002; 45: 268-281
        • Alku P
        • Airas M
        • Björkner E
        • et al.
        An amplitude quotient based method to analyze changes in the shape of the glottal pulse in the regulation of vocal intensity.
        J Acoust Soc Am. 2006; 120 (Aug): 1052-1062
        • Dietrich M
        • Andreatta RD
        • Jiang Y
        • et al.
        Preliminary findings on the relation between the personality trait of stress reaction and the central neural control of human vocalization.
        Int J Speech Lang Pathol. 2012; 14 (Aug): 377-389
        • Jones K
        • Sigmon J
        • Hock L
        • et al.
        Prevalence and risk factors for voice problems among telemarketers.
        Arch Otolaryngol - Head Neck Surg. 2002; 128 ([Internet]Available from): 571-577
      4. Vilkman E. Voice problems at work: a challenge for occupational safety and health arrangement. In: Folia Phoniatrica et Logopaedica [Internet]. Folia Phoniatr Logop; 2000 [cited 2021 May 21]. p. 120–5. Available from:

        • Verdolini K.
        • Ramig LO
        • Verdolini K.
        • et al.
        Occupational risks for voice problems.
        Logopedics Phoniatrics Vocology. 2001; 26 (2001): 37-46