Journal of Epidemiology and Global Health

Volume 11, Issue 2, June 2021, Pages 143 - 145

Role of Ascertainment Bias in Determining Case Fatality Rate of COVID-19

Authors
Maia P. Smith*, ORCID
Department of Public Health and Preventive Medicine, St. George’s University School of Medicine, True Blue, Grenada, West Indies
Corresponding Author
Maia P. Smith
Received 22 September 2020, Accepted 17 March 2021, Available Online 8 April 2021.
DOI
https://doi.org/10.2991/jegh.k.210401.001How to use a DOI?
Keywords
Epidemiology; health policy; ascertainment bias; Global health; bias; epidemiologic methods; Africa; Asia; Europe; North America; South America; virus; COVID-19; SARS-COV-2; log-log linear regression; log slope
Abstract

Case fatality rate (CFR) is used to calculate mortality burden of COVID-19 under different scenarios, thus informing risk-benefit balance of interventions both pharmaceutical and nonpharmaceutical. However, observed CFR is driven by testing: as more low-risk cases are identified, observed CFR will decline. This report quantifies test bias by modeling observed CFR as log-log-linear function of test density (tests per population) in 163 countries. CFR declined almost 20% (e.g. from 5% to 4%) for each doubling of test density (p < 0.0001); this association did not vary by continent (interaction p > 0.10) although at any given test density CFR was higher in Europe or North America than in Asia or Africa. This effect of test density on observed CFR is adequate to hide all but the largest true differences in case survivorship. Published estimates of CFR should specify test density, and comparisons should correct for it such as by applying the provided model.

Copyright
© 2021 The Author. Published by Atlantis Press International B.V.
Open Access
This is an open access article distributed under the CC BY-NC 4.0 license (http://creativecommons.org/licenses/by-nc/4.0/).

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Journal
Journal of Epidemiology and Global Health
Volume-Issue
11 - 2
Pages
143 - 145
Publication Date
2021/04/08
ISSN (Online)
2210-6014
ISSN (Print)
2210-6006
DOI
https://doi.org/10.2991/jegh.k.210401.001How to use a DOI?
Copyright
© 2021 The Author. Published by Atlantis Press International B.V.
Open Access
This is an open access article distributed under the CC BY-NC 4.0 license (http://creativecommons.org/licenses/by-nc/4.0/).

Cite this article

TY  - JOUR
AU  - Maia P. Smith
PY  - 2021
DA  - 2021/04/08
TI  - Role of Ascertainment Bias in Determining Case Fatality Rate of COVID-19
JO  - Journal of Epidemiology and Global Health
SP  - 143
EP  - 145
VL  - 11
IS  - 2
SN  - 2210-6014
UR  - https://doi.org/10.2991/jegh.k.210401.001
DO  - https://doi.org/10.2991/jegh.k.210401.001
ID  - Smith2021
ER  -