Evidence map›Paper›PMID 34921199›Full record

ArticleScientific reports2021

Spatiotemporal droplet dispersion measurements demonstrate face masks reduce risks from singing.

Kai Man Alexander Ho, Hywel Davies, Ruth Epstein, Paul Bassett, Áine Hogan, Yusuf Kabir, John Rubin, Gee Yen Shin, Jonathan P Reid, Ryo Torii and 3 more

Open access · goldAbstract read
In one paragraph

Article in Scientific reports, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 5 papers, 1 of them a synthesis that pooled it.

0numbers the graph read from it
0cells of the map it votes in
5citing papers in PubMed, 1 pooled it
1.5field-weighted citation impact, top 16% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

5 citing papers in PubMed, 1 synthesis or guideline pooled it, 15 citations in OpenAlex.

  1. Pooled it
  2. Article
  3. Review
  4. Article
  5. Article
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

13 authors at 5 institutions in 1 country.

Kai Man Alexander Ho *Wellcome / EPSRC Centre for Interventional and Surgical Sciences (WEISS), University College London, Charles Bell House, 43-45 Foley Street, London, W1W 7TY, UK. alexander.ho@ucl.ac.uk.
Hywel Davies *Department of Mechanical Engineering, University College London, Malet Place, London, WC1E 6BT, UK.
Ruth EpsteinDepartment of Otolaryngology, Royal National Ear Nose and Throat and Eastman Dental Hospital, University College London Hospitals NHS Foundation Trust, 47-49 Huntley Street, London, WC1E 6DG, UK.
Paul BassettStatsconsultancy Ltd, 40 Longwood Lane, Amersham, Bucks, HP7 9EN, UK.
Áine HoganWellcome / EPSRC Centre for Interventional and Surgical Sciences (WEISS), University College London, Charles Bell House, 43-45 Foley Street, London, W1W 7TY, UK.
Yusuf KabirWellcome / EPSRC Centre for Interventional and Surgical Sciences (WEISS), University College London, Charles Bell House, 43-45 Foley Street, London, W1W 7TY, UK.
John RubinDepartment of Otolaryngology, Royal National Ear Nose and Throat and Eastman Dental Hospital, University College London Hospitals NHS Foundation Trust, 47-49 Huntley Street, London, WC1E 6DG, UK.
Gee Yen ShinDepartment of Virology, University College London Hospitals NHS Foundation Trust, 250 Euston Road, London, NW1 2PG, UK.
Jonathan P ReidSchool of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK.
Ryo ToriiDepartment of Mechanical Engineering, University College London, Malet Place, London, WC1E 6BT, UK.
Manish K TiwariWellcome / EPSRC Centre for Interventional and Surgical Sciences (WEISS), University College London, Charles Bell House, 43-45 Foley Street, London, W1W 7TY, UK.
Ramanarayanan BalachandranDepartment of Mechanical Engineering, University College London, Malet Place, London, WC1E 6BT, UK.
Laurence B LovatWellcome / EPSRC Centre for Interventional and Surgical Sciences (WEISS), University College London, Charles Bell House, 43-45 Foley Street, London, W1W 7TY, UK.
University College London · GBUniversity College London Hospitals NHS Foundation Trust · GBEastman Dental Hospital · GBUniversity of Bristol · GBWellcome / EPSRC Centre for Interventional and Surgical Sciences · GB

Funding

Wellcome TrustWellcome Trust 203145Z/16/Z
6 · The paper itself

Abstract

COVID-19 has restricted singing in communal worship. We sought to understand variations in droplet transmission and the impact of wearing face masks. Using rapid laser planar imaging, we measured droplets while participants exhaled, said 'hello' or 'snake', sang a note or 'Happy Birthday', with and without surgical face masks. We measured mean velocity magnitude (MVM), time averaged droplet number (TADN) and maximum droplet number (MDN). Multilevel regression models were used. In 20 participants, sound intensity was 71 dB for speaking and 85 dB for singing (p < 0.001). MVM was similar for all tasks with no clear hierarchy between vocal tasks or people and > 85% reduction wearing face masks. Droplet transmission varied widely, particularly for singing. Masks decreased TADN by 99% (p < 0.001) and MDN by 98% (p < 0.001) for singing and 86-97% for other tasks. Masks reduced variance by up to 48%. When wearing a mask, neither singing task transmitted more droplets than exhaling. In conclusion, wide variation exists for droplet production. This significantly reduced when wearing face masks. Singing during religious worship wearing a face mask appears as safe as exhaling or talking. This has implications for UK public health guidance during the COVID-19 pandemic.

Indexed as

FaceMasksAdultCOVID-19Cross-Sectional StudiesDisease Transmission, InfectiousExhalationFemaleHumansMalePandemicsRisk FactorsSARS-CoV-2SingingVirus Shedding

Identifiers

PMID34921199
PMCPMC8683488
OpenAlexW4200272703

What OpenQuestion holds

Textmetadata
LicenceCC BY
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.