Calculating the prevalence of soil-transmitted helminth infection through pooling of stool samples: Choosing and optimizing the pooling strategy.
Prevalence is a common epidemiological measure for assessing soil-transmitted helminth burden and forms the basis for much public-health decision-making. Standard diagnostic techniques are based on egg detection in stool samples through microscopy and these techniques are known to have poor sensitiv...
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ftdoajarticles:oai:doaj.org/article:dc3ea344ef6c47348a82106022b229ab 2023-05-15T15:12:13+02:00 Calculating the prevalence of soil-transmitted helminth infection through pooling of stool samples: Choosing and optimizing the pooling strategy. James E Truscott Julia C Dunn Marina Papaiakovou Fabian Schaer Marleen Werkman D Timothy J Littlewood Judd L Walson Roy M Anderson 2019-03-01T00:00:00Z https://doi.org/10.1371/journal.pntd.0007196 https://doaj.org/article/dc3ea344ef6c47348a82106022b229ab EN eng Public Library of Science (PLoS) https://doi.org/10.1371/journal.pntd.0007196 https://doaj.org/toc/1935-2727 https://doaj.org/toc/1935-2735 1935-2727 1935-2735 doi:10.1371/journal.pntd.0007196 https://doaj.org/article/dc3ea344ef6c47348a82106022b229ab PLoS Neglected Tropical Diseases, Vol 13, Iss 3, p e0007196 (2019) Arctic medicine. Tropical medicine RC955-962 Public aspects of medicine RA1-1270 article 2019 ftdoajarticles https://doi.org/10.1371/journal.pntd.0007196 2022-12-31T13:17:57Z Prevalence is a common epidemiological measure for assessing soil-transmitted helminth burden and forms the basis for much public-health decision-making. Standard diagnostic techniques are based on egg detection in stool samples through microscopy and these techniques are known to have poor sensitivity for individuals with low infection intensity, leading to poor sensitivity in low prevalence populations. PCR diagnostic techniques offer very high sensitivities even at low prevalence, but at a greater cost for each diagnostic test in terms of equipment needed and technician time and training. Pooling of samples can allow prevalence to be estimated while minimizing the number of tests performed. We develop a model of the relative cost of pooling to estimate prevalence, compared to the direct approach of testing all samples individually. Analysis shows how expected relative cost depends on both the underlying prevalence in the population and the size of the pools constructed. A critical prevalence level (approx. 31%) above which pooling is never cost effective, independent of pool size. When no prevalence information is available, there is no basis on which to choose between pooling and testing all samples individually. We recast our model of relative cost in a Bayesian framework in order to investigate how prior information about prevalence in a given population can be used to inform the decision to choose either pooling or full testing. Results suggest that if prevalence is below 10%, a relatively small exploratory prevalence survey (10-15 samples) can be sufficient to give a high degree of certainty that pooling may be relatively cost effective. Article in Journal/Newspaper Arctic Directory of Open Access Journals: DOAJ Articles Arctic PLOS Neglected Tropical Diseases 13 3 e0007196 |
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Open Polar |
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Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
Arctic medicine. Tropical medicine RC955-962 Public aspects of medicine RA1-1270 |
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Arctic medicine. Tropical medicine RC955-962 Public aspects of medicine RA1-1270 James E Truscott Julia C Dunn Marina Papaiakovou Fabian Schaer Marleen Werkman D Timothy J Littlewood Judd L Walson Roy M Anderson Calculating the prevalence of soil-transmitted helminth infection through pooling of stool samples: Choosing and optimizing the pooling strategy. |
topic_facet |
Arctic medicine. Tropical medicine RC955-962 Public aspects of medicine RA1-1270 |
description |
Prevalence is a common epidemiological measure for assessing soil-transmitted helminth burden and forms the basis for much public-health decision-making. Standard diagnostic techniques are based on egg detection in stool samples through microscopy and these techniques are known to have poor sensitivity for individuals with low infection intensity, leading to poor sensitivity in low prevalence populations. PCR diagnostic techniques offer very high sensitivities even at low prevalence, but at a greater cost for each diagnostic test in terms of equipment needed and technician time and training. Pooling of samples can allow prevalence to be estimated while minimizing the number of tests performed. We develop a model of the relative cost of pooling to estimate prevalence, compared to the direct approach of testing all samples individually. Analysis shows how expected relative cost depends on both the underlying prevalence in the population and the size of the pools constructed. A critical prevalence level (approx. 31%) above which pooling is never cost effective, independent of pool size. When no prevalence information is available, there is no basis on which to choose between pooling and testing all samples individually. We recast our model of relative cost in a Bayesian framework in order to investigate how prior information about prevalence in a given population can be used to inform the decision to choose either pooling or full testing. Results suggest that if prevalence is below 10%, a relatively small exploratory prevalence survey (10-15 samples) can be sufficient to give a high degree of certainty that pooling may be relatively cost effective. |
format |
Article in Journal/Newspaper |
author |
James E Truscott Julia C Dunn Marina Papaiakovou Fabian Schaer Marleen Werkman D Timothy J Littlewood Judd L Walson Roy M Anderson |
author_facet |
James E Truscott Julia C Dunn Marina Papaiakovou Fabian Schaer Marleen Werkman D Timothy J Littlewood Judd L Walson Roy M Anderson |
author_sort |
James E Truscott |
title |
Calculating the prevalence of soil-transmitted helminth infection through pooling of stool samples: Choosing and optimizing the pooling strategy. |
title_short |
Calculating the prevalence of soil-transmitted helminth infection through pooling of stool samples: Choosing and optimizing the pooling strategy. |
title_full |
Calculating the prevalence of soil-transmitted helminth infection through pooling of stool samples: Choosing and optimizing the pooling strategy. |
title_fullStr |
Calculating the prevalence of soil-transmitted helminth infection through pooling of stool samples: Choosing and optimizing the pooling strategy. |
title_full_unstemmed |
Calculating the prevalence of soil-transmitted helminth infection through pooling of stool samples: Choosing and optimizing the pooling strategy. |
title_sort |
calculating the prevalence of soil-transmitted helminth infection through pooling of stool samples: choosing and optimizing the pooling strategy. |
publisher |
Public Library of Science (PLoS) |
publishDate |
2019 |
url |
https://doi.org/10.1371/journal.pntd.0007196 https://doaj.org/article/dc3ea344ef6c47348a82106022b229ab |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
Arctic |
genre_facet |
Arctic |
op_source |
PLoS Neglected Tropical Diseases, Vol 13, Iss 3, p e0007196 (2019) |
op_relation |
https://doi.org/10.1371/journal.pntd.0007196 https://doaj.org/toc/1935-2727 https://doaj.org/toc/1935-2735 1935-2727 1935-2735 doi:10.1371/journal.pntd.0007196 https://doaj.org/article/dc3ea344ef6c47348a82106022b229ab |
op_doi |
https://doi.org/10.1371/journal.pntd.0007196 |
container_title |
PLOS Neglected Tropical Diseases |
container_volume |
13 |
container_issue |
3 |
container_start_page |
e0007196 |
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1766342938119372800 |