Abstract
Objective
Study Design
Materials and Methods
Results
Conclusion
Key Words
INTRODUCTION
World Health Organization. WHO Director-General's opening remarks at the media briefing on COVID-19 - 11. 2020. Available at:https://www.who.int/dg/speeches/detail/who-director-general-s-opening-remarks-at-the-media-briefing-on-covid-19—11-march-2020. Accessed March 11, 2020.
Bench press. The difference between N95s, surgical masks and cloth masks. 2020. Available at: https://mgriblog.org/2020/04/29/the-difference-between-n95s-surgical-masks-and-cloth-masks/. Accessed on 29 April.
Bench press. The difference between N95s, surgical masks and cloth masks. 2020. Available at: https://mgriblog.org/2020/04/29/the-difference-between-n95s-surgical-masks-and-cloth-masks/. Accessed on 29 April.
METHOD

Keywords | Synonyms |
---|---|
#1 | "Effect" OR "influence" OR "impact" |
#2 | "Face mask" OR "face cover" OR "face guard" OR "face shield" OR "respirator" OR "mask filter" |
#3 | "Voice" OR "speech" OR "speaking" OR "talking" OR "communication" |
#4 | "COVID-19″ OR "2019 coronavirus disease" OR "coronavirus disease 2019″ OR "2019 novel coronavirus" OR "2019-new coronavirus" OR "2019-nCoV" OR "coronavirus" OR "COVID" OR "corona" OR "SARS-CoV-2″ |
Item | Questions |
---|---|
1. | Was the research objective clearly stated? |
2. | Was the study population specified and defined? |
3. | Were all the participants recruited from the same population in the same period? |
4. | Were inclusion and exclusion criteria for the participants defined in the study? |
5. | Was the research design mentioned? |
6. | Was the sampling method mentioned? |
7. | Was the pilot study tested or reviewed before the actual study? |
8. | Was the sample size justification provided? |
9. | Were the outcome measures defined clearly? |
10. | Were ethical approval and informed consent obtained? |
11. | Was the order of 'mask condition' and 'no mask condition’ randomized? |
12. | Were the outcome assessors (or raters) blinded to the participants' exposures/interventions (‘mask condition' and 'no mask condition’)? |
13. | Was the loss to follow-up after baseline testing (mask condition /no mask condition) 20% or less? |
14. | Were the tools tested for their reliability and validity? |
15. | Was the statistical analysis appropriate to answer the research question? |
16. | Was there a mention of the settings under which the findings could be applied? |
RESULTS
Study ID | Items | Quality appraisal score (%) | |||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | ||
Ribeiro et al 14 | 1 | 1 | 1 | 1 | 1 | 0 | 0 | 0 | 1 | 1 | 0 | 0 | 1 | 0 | 1 | 1 | 62.50 |
Heider et al 15 | 1 | 1 | 1 | 1 | 1 | 0 | 0 | 1 | 1 | 1 | 0 | 0 | 1 | 0 | 1 | 1 | 68.75 |
Corey et al 25 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 1 | 0 | 0 | 1 | 0 | 1 | 1 | 37.5 |
Bottalico et al 26 | 1 | 1 | 1 | 1 | 0 | 0 | 1 | 1 | 1 | 1 | 0 | 0 | 1 | 0 | 1 | 1 | 68.75 |
Cavallaro et al 27 | 1 | 1 | 1 | 1 | 0 | 0 | 0 | 0 | 1 | 1 | 0 | 0 | 1 | 0 | 1 | 1 | 56.25 |
Magee et al 28 | 1 | 1 | 1 | 1 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 1 | 1 | 1 | 1 | 1 | 62.50 |
Fiorella et al 29 | 1 | 1 | 1 | 1 | 0 | 0 | 0 | 0 | 1 | 1 | 0 | 0 | 1 | 0 | 1 | 1 | 56.25 |
Nguyen et al 30 | 1 | 1 | 1 | 1 | 1 | 0 | 0 | 0 | 1 | 1 | 1 | 0 | 1 | 1 | 1 | 1 | 75.00 |
Rahne et al 31 | 1 | 1 | 1 | 1 | 1 | 0 | 0 | 0 | 1 | 1 | 0 | 0 | 1 | 0 | 1 | 1 | 62.5 |
Lin et al 32 | 1 | 1 | 1 | 1 | 0 | 0 | 0 | 0 | 1 | 1 | 0 | 0 | 1 | 0 | 1 | 1 | 56.25 |
Study ID | Title of the study | Time of publication | Place of study | Type of mask studied and Manufacturer |
---|---|---|---|---|
14 | Effect of Wearing a Face Mask on Vocal Self-Perception during a Pandemic | 1st October 2020 | Federal University of Sergipe, Sergipe, Brazil | N95 mask, disposable mask, and cloth mask |
15 | Prevalence of Voice Disorders in Healthcare Workers in the Universal Masking COVID-19 Era | 2nd October 2020 | Santiago, USA | Surgical mask and self-filtering mask |
25 | Acoustic effects of medical, cloth, and transparent face masks on speech signals | 27th October 2020 | The University of Illinois at Urbana-Champaign, Urbana, Illinois, USA | Surgical mask, N95 respirator, KN95 respirator, six cloth masks of a different fabric (cotton, jersey, spandex, denim, bedsheet polyester), and two cloth masks with a transparent window (Vinyl window & polyvinyl chloride window) |
26 | Effect of masks on speech intelligibility in auralized classrooms | 24th November 2020 | The University of Illinois at Urbana-Champaign Illinois, USA | Fabric mask, Surgical mask, N95 mask, and an elastomeric half-mask air-purifying respirator (EAPR) |
27 | Acoustic voice analysis in the COVID-19 era | 24th November 2020 | University of Bari “Aldo Moro”, Italy | Surgical mask |
28 | Effects of face masks on acoustic analysis and speech perception: Implications for peri-pandemic protocols | 10th December 2020 | The University of Melbourne, Australia | Standard surgical mask (Regulated under 21 CFR 878.4040), Cloth mask (2-layered cotton), and N95 mask (Electrostatic non-woven polypropylene fiber containing a filtration layer) |
29 | Voice Differences When Wearing and Not Wearing a Surgical Mask | 10th March 2021 | University of Bari, Bari, Italy | Surgical mask-the three-ply material consists of a melt-blown polymer, most commonly polypropylene, placed between two layers of non-woven fabric |
30 | Acoustic voice characteristics with and without wearing a facemask | 11th March 2021 | University of Sydney, Sydney, Australia | Surgical mask and KN95 mask |
31 | Influence of face surgical and N95 face 2 masks on speech perception and 3 listening effort in noise | 23rd March 2021 (pre-print) | Martin Luther University Halle Wittenberg, Germany | Foliodress LOOP TYPE IIR surgical face masks (CMC Medical Devices & Drugs, Malaga, Spain) according to European standard EN 14683 and 95 mask -RSN95B FFP2 NR particle filtering half masks (Rysam Medical Equipment Manufacturing, Donguan City, China) |
32 | Effects of Medical Masks on Voice Assessment During the COVID-19 Pandemic. | 27th April 2021 (pre-print) | Beijing Tongren Hospital, Capital Medical University, Beijing, China. | Medical mask |
Study ID | Study design/ Participants (n)/gender, age range | Inclusion/ Exclusion criteria | Participants’ profession | Type of questionnaire/ instrument used- task | Measures studied | Findings during ‘no mask’ condition | Findings during ‘mask’ condition | Level of evidence |
---|---|---|---|---|---|---|---|---|
14 | Cross-sectional; n = 468 (122 males, 346 females); 18 – 59 years | Individuals diagnosed with a voice disorder/ COVID-19, and non-residents of Brazil were excluded. | Wearing a mask for professional and essential activities during the pandemic (WG group); Wearing mask only to perform essential activities during the pandemic (EAG group). | VFI - Brazilian Portuguese version 33 | VFI total mean score | - | WG = 21.66±8.99; EAG = 19.61±7.96 | Low |
Self-perception of VTDS - Brazilian Portuguese version 34 | VTDS frequency subscale total mean score | - | WG = 7.87; EAG = 4.98 | |||||
VTDS severity subscale total mean score | - | WG = 14.72; EAG = 9.44 | ||||||
Self-perception of vocal effort Likert rating scale 14 | Vocal effort mean score | WG = 0.66±0.90; EAG = 0.57±0.72 | WG = 2.28 EAG = 1.99 | |||||
15 | Cross-sectional; n = 221 (54 males, 167 females); 18 – 59 years | Three groups of participants: Group I-44 hours/week shift with 8 hours daily; Group II-22 hours/week shift with 4 hours daily; Group III-Fourth shift modality with 24 hours on-duty followed by 3 days off. | Nurses, physicians, medical residents, physical therapists, speech-language pathologists (SLP), and nursing assistants | Self-Perceived Voice Symptoms -23 item questionnaire survey | No. of participants (%) | - | 67.43% (147) no voice problem, 21.56% (47) mild and 11.10% (24) severe | Low |
Spanish validated VHI-10 35 | VHI score | - | 160 had normal score & 58 abnormal scores (>11) | |||||
25 | n = 1 | Not stated | Not stated | Speechreading recorded for 30 s | Sound level attenuation (dB) | - | Transparent – 8; Cloth - 6.36; N95 – 5.4; Surgical – 2.8; KN95 – 2.6; Peak attenuation (>1 kHz): N95 – 6; Surgical; KN95 – 4 | Low |
26 | n = 1, male | A male speaker with a standard American English dialect. | Not stated | ‘Consonant-Nucleus-Consonant (CNC)’ word list of monosyllabic words with equal phonemic distribution 36 , 37 recorded using compact disc 38 | Sound level attenuation dB | - | Fabric – 4.2; N95 – 2.9; Surgical – 2.3 | Low |
27 | n = 50 (20 males, 30 females); 26 – 69 years | Individuals with an ability to sustain vowels for at least 10 s were included. Individuals with a current or history of voice disorder and voice therapy taken, or with a history of respiratory infection in 2 weeks before recording, were excluded. | Not stated | ‘Praat’ software (version 6.1.16)-Sustained vowel /a/ at comfortable pitch and loudness. | Mean pitch (Hz) | 185.52± 55.12 | 183.52±51.13 | Low |
Number of pulses | 575.00± 168.76 | 574.18±157.88 | ||||||
Mean HNR | 20.92±3.47 | 20.91±3.44 | ||||||
Jitter (%) | 0.298± 0.124 | 0.327± 0.134 | ||||||
Shimmer (%) | 3.165 ±1.572 | 3.34 ±1.420 | ||||||
28 | n = 7 (4 males, 3 females); 21 – 39 years | Individuals with English speaking ability and with no history of voice, cognition, neurological impairments were included. | Not stated | ‘Praat’ -Sustained vowel /a/; Reading phonetically balanced ‘Grandfather Passage’ 40 text | Mean intensity (dB) | 71.54±3.89 | Surgical-71.73±4.34; N95-71.85±4.31; Cloth-72.26±2.78 | Moderate |
p95 Intensity | 72.66±3.76 | Surgical-72.87±4.3; N95-72.95±4.37; Cloth-73.52±2.84 | ||||||
Mean f0 frequency (Hz) | 155.80±63.25 | Surgical-155.4±64.64; N95-156.4±61.32; Cloth-169.77±45.03 | ||||||
f0 CoV (%) | 0.71±0.09 | Surgical-0.77±0.08; N95-0.65±0.08; Cloth-0.65±0.06 | ||||||
CPPS (dB) | 19.52±2.74 | Surgical-19.16±1.87; N95-19.99±2.19; Cloth- 19.34±2.1 | ||||||
HNR | 20.30±3.66 | Surgical -19.11±3.25; N95-21.88±3.77; Cloth-21.37±2.16 | ||||||
Jitter (%) | 0.32±0.06 | Surgical -0.36±0.11; N95-0.31±0.08; Cloth 0.32±0.06 | ||||||
Shimmer (%) | 1.51±0.23 | Surgical -1.55±0.16;N95-1.64±0.5; Cloth 1.51±0.24 | ||||||
Spectral tilt (dB) | -30.82±1.43dB* | Surgical:-24.78±1.82* N95:-23.59±4.09*; Cloth:-29.32±4.96 | ||||||
29 | n = 60 (24 males, 36 females), 26 – 69 years | Individuals with the ability to sustain a vowel for at least 10 s were included. Individuals with a current or history of voice disorder and voice therapy, or with a history of respiratory infection in 2 weeks before recording, were excluded. | Workers of the ENT Department of the Polyclinic Hospital, University of Bari “Aldo Moro”, Italy. | ‘Praat’ 41 Sustained vowel /a/ at comfortable pitch and loudness.Boersma P, Weenink D. Praat: doing phonetics by computer Available at: http://www.fon.hum.uva.nl/praat/2018. Accessed August 5, 2020. | MPT(s) | 25.58±5.79 for males, 20.64±3.97 for females | Surgical - 25.29±5.52 for males, 19.86±4.17 for females | Low |
Mean f0 frequency (Hz) | 131.8±24.40 for males, 213.34±41.40 for females | Surgical - 132.27±24.33 for males, 211.19±33.38 for females | ||||||
Mean Vocal intensity (dB) | 68.54±6.72 for males, 70.07±5.88 for females | Surgical - 68.67±6.48 for males, 68.07±6.14 for females | ||||||
No. of glottal pulses | 429.08±111.91 for males, 644.47±136.54 for females | Surgical - 427.83±98.71 for males, 653.86±109.64 for females | ||||||
No. of periods | 428.08±111.91 for males, 643.47±136.54 for females | Surgical - 426.79±98.74 for males, 652.75±109.66 for females | ||||||
Mean HNR (dB) | 18.91±3.80 for males, 21.08±3.76 for females | Surgical - 19.46±4.08 for males, 20.87±3.46 for females | ||||||
Jitter (%) | 0.38±0.26 for males, 0.30±0.12 for females | Surgical - 0.36±0.16 for males, 0.34±0.12 for females | ||||||
Shimmer (%) | 4.45±1.22 for males, 2.98±1.22 for females | Surgical - 3.92±2.21 for males, 3.51±1.64 for females | ||||||
30 | Within-subject study design; n = 16 (4 males, 12 females) | Individuals speaking English and without smoking habits, voice, hearing problems were included. | Otolaryngologists, SLPs, and a Nurse | ‘Praat’ 41 -Sustained vowel /a/ for at least 10s; Reading 3rd phrase of ‘CAPE-V’ Boersma P, Weenink D. Praat: doing phonetics by computer Available at: http://www.fon.hum.uva.nl/praat/2018. Accessed August 5, 2020. 42 and 2nd and 3rd sentences of ‘Rainbow’ passage- 43 . | Mean spectral level at low (0-1kHz) & high frequency (1-8kHz) | - | KN95 -5.2 dB* Surgical - 2dB * | Moderate |
Low/High Spectral ratio (0-1kHz/1-8kHz) | 23 ±1.7 dB | KN95 -28.2 ±1.7 dB*, Surgical -25.5 ±2.2dB* | ||||||
HNR ratio | 25.0 ±3.5 | KN95 -28.4±4.1 dB*, Surgical - 27.3 ±4.5 dB* | ||||||
CPPS (dB) | No significant difference between unmasked and masked conditions | |||||||
Vocal intensity (dB) | 64.0±7.0 | Surgical-65.8±7.2 KN95-66.7±7.5 | ||||||
31 | Prospective exploratory experimental, n = 2 (1 male, 1 female) | Not stated | Not stated | 20 sentences from ‘German matrix Oldenburg Sentence test’ (OLSA) 44
Entwicklung und evaluation eines satztests für die deutsche sprache. I-III: design, optimierung und evaluation des oldenburger satztests (development and evaluation of a sentence test for the german language. I-III: design, optimization and evaluation of the Oldenburg sentence test). Zeitschrift für Audiol (Audiological Acoustics). 1999; 38: 4-15 | Sound level attenuation (dB) | - | For Olnoise female, Olnoise male and ISTS noise 45 : N95-8 dB at 2.52 and 5.04 kHz; Surgical- 8 dB at 8kHz kHzFor white noise: N95-4.1 dB; Surgical-2.6 dB | Low |
32 | n = 53 (25 males, 28 females); 20 – 68 years | Participants with normal voice, no history of voice/ articulation/ anatomical problems, voice therapy, and vocal tract surgery, were included. | Not stated | ‘MDVP’ (Version 3.3.0, Kay Pentax) &‘Praat’ (version 6.1.13)-Sustained vowel /a/ at comfortable pitch and loudness for at least 3 s for acoustic measures, and as long as possible for MPT measure. | f0 (Hz) | 130.51±21.98 – male;224.46±27.09 - female | Surgical:133.00±21.03-male; 228.91±27.28 - female | Low |
SPL(dB) | 72.58±4.13 – male; 70.00±4.04 - female | Surgical:73.59±3.54-male, 71.37±4.08; female | ||||||
Jitter (%) | 1.14±0.72-male; 1.24±0.92-female | Surgical:0.75±0.63- male; 0.98±0.69 -female | ||||||
Shimmer (%) | 4.44±2.83- male; 4.53±1.48 -female | Surgical:3.30±1.31- male; 3.98±0.69 -female | ||||||
NHR (dB) | 0.13±0.03-male and female | Surgical: 0.13±0.02- male; 0.13±0.03-female | ||||||
CPP (dB) | 12.43±4.01- male; 12.63±3.91-female | Surgical:11.47±3.67 – male; 12.14±4.88 female | ||||||
MPT(s) | 20.36±7.38- male;16.36±6.11- female | Surgical:19.88±7.69 –male;17.21±7.39-female |
DISCUSSION
Self-reported measures of voice
Acoustic measures of voice
- Frisancho K
- Salfate L
- Lizana K
- et al.
Aerodynamic measures of voice
Limitations and further recommendations
CONCLUSION
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Conflict of Interests: Both the authors declare that they have no conflict of interest.