Evidence map›Paper›PMID 33361331›Full record

ArticleProceedings of the National Academy of Sciences of the United States of America2021

Forward-looking serial intervals correctly link epidemic growth to reproduction numbers.

Sang Woo Park, Kaiyuan Sun, David Champredon, Michael Li, Benjamin M Bolker, David J D Earn, Joshua S Weitz, Bryan T Grenfell, Jonathan Dushoff

Abstract read
In one paragraph

Article in Proceedings of the National Academy of Sciences of the United States of America, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 44 papers, 2 of them syntheses that pooled it.

0numbers the graph read from it
0cells of the map it votes in
44citing papers in PubMed, 2 pooled it
–field-weighted citation impact
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

44 citing papers in PubMed, 2 syntheses or guidelines pooled it.

  1. Pooled it
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  9. Mathematical modelling for pandemic preparedness in Canada: Learning from COVID-19.Canada communicable disease report = Releve des maladies transmissibles au Canada · 2024
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  12. Incorporating testing volume into estimation of effective reproduction number dynamics.Journal of the Royal Statistical Society. Series A, (Statistics in Society) · 2024
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  13. Article
  14. Article
  15. Rates of SARS-CoV-2 transmission between and into California state prisons.medRxiv : the preprint server for health sciences · 2023
    Article
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  17. Estimated incubation period distributions of mpox using cases from two international European festivals and outbreaks in a club in Berlin, May to June 2022.Euro surveillance : bulletin Europeen sur les maladies transmissibles = European communicable disease bulletin · 2023
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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

9 authors.

Sang Woo ParkDepartment of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ 08544; swp2@princeton.edu.ORCID 0000-0003-2202-3361
Kaiyuan SunDivision of International Epidemiology and Population Studies, Fogarty International Center, NIH, Bethesda, MD 20892.ORCID 0000-0002-1753-9884
David ChampredonDepartment of Pathology and Laboratory Medicine, University of Western Ontario, London, ON N6A 3K7, Canada.
Michael LiDepartment of Biology, McMaster University, Hamilton, ON L8S 4L8, Canada.ORCID 0000-0001-5150-8662
Benjamin M BolkerDepartment of Biology, McMaster University, Hamilton, ON L8S 4L8, Canada.
David J D EarnDepartment of Mathematics and Statistics, McMaster University, Hamilton, ON L8S 4L8, Canada.ORCID 0000-0002-7562-1341
Joshua S WeitzSchool of Biological Sciences, Georgia Institute of Technology, Atlanta, GA 30332.ORCID 0000-0002-3433-8312
Bryan T GrenfellDepartment of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ 08544.
Jonathan DushoffDepartment of Biology, McMaster University, Hamilton, ON L8S 4L8, Canada.ORCID 0000-0003-0506-4794

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

The reproduction number R and the growth rate r are critical epidemiological quantities. They are linked by generation intervals, the time between infection and onward transmission. Because generation intervals are difficult to observe, epidemiologists often substitute serial intervals, the time between symptom onset in successive links in a transmission chain. Recent studies suggest that such substitution biases estimates of R based on r. Here we explore how these intervals vary over the course of an epidemic, and the implications for R estimation. Forward-looking serial intervals, measuring time forward from symptom onset of an infector, correctly describe the renewal process of symptomatic cases and therefore reliably link R with r. In contrast, backward-looking intervals, which measure time backward, and intrinsic intervals, which neglect population-level dynamics, give incorrect R estimates. Forward-looking intervals are affected both by epidemic dynamics and by censoring, changing in complex ways over the course of an epidemic. We present a heuristic method for addressing biases that arise from neglecting changes in serial intervals. We apply the method to early (21 January to February 8, 2020) serial interval-based estimates of R for the COVID-19 outbreak in China outside Hubei province; using improperly defined serial intervals in this context biases estimates of initial R by up to a factor of 2.6. This study demonstrates the importance of early contact tracing efforts and provides a framework for reassessing generation intervals, serial intervals, and R estimates for COVID-19.

Indexed as

Basic Reproduction NumberModels, TheoreticalChinaCOVID-19Humansgeneration intervalinfectious disease modelingreproduction numberserial interval

Identifiers

PMID33361331
PMCPMC7812760

What OpenQuestion holds

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LicenceCC BY
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Registered trials

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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.