Bayesian Latent Class Models in malaria diagnosis.

AIMS: The main focus of this study is to illustrate the importance of the statistical analysis in the evaluation of the accuracy of malaria diagnostic tests, without admitting a reference test, exploring a dataset (n=3317) collected in São Tomé and Príncipe. METHODS: Bayesian Latent Class Models (wi...

Full description

Bibliographic Details
Main Authors: Luzia Gonçalves, Ana Subtil, M Rosário de Oliveira, Virgílio do Rosário, Pei-Wen Lee, Men-Fang Shaio
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2012-01-01
Series:PLoS ONE
Online Access:http://europepmc.org/articles/PMC3402519?pdf=render
_version_ 1819238229651488768
author Luzia Gonçalves
Ana Subtil
M Rosário de Oliveira
Virgílio do Rosário
Pei-Wen Lee
Men-Fang Shaio
author_facet Luzia Gonçalves
Ana Subtil
M Rosário de Oliveira
Virgílio do Rosário
Pei-Wen Lee
Men-Fang Shaio
author_sort Luzia Gonçalves
collection DOAJ
description AIMS: The main focus of this study is to illustrate the importance of the statistical analysis in the evaluation of the accuracy of malaria diagnostic tests, without admitting a reference test, exploring a dataset (n=3317) collected in São Tomé and Príncipe. METHODS: Bayesian Latent Class Models (without and with constraints) are used to estimate the malaria infection prevalence, together with sensitivities, specificities, and predictive values of three diagnostic tests (RDT, Microscopy and PCR), in four subpopulations simultaneously based on a stratified analysis by age groups (< 5, ≥ 5 years old) and fever status (febrile, afebrile). RESULTS: In the afebrile individuals with at least five years old, the posterior mean of the malaria infection prevalence is 3.2% with a highest posterior density interval of [2.3-4.1]. The other three subpopulations (febrile ≥ 5 years, afebrile or febrile children less than 5 years) present a higher prevalence around 10.3% [8.8-11.7]. In afebrile children under-five years old, the sensitivity of microscopy is 50.5% [37.7-63.2]. In children under-five, the estimated sensitivities/specificities of RDT are 95.4% [90.3-99.5]/93.8% [91.6-96.0]--afebrile--and 94.1% [87.5-99.4]/97.5% [95.5-99.3]--febrile. In individuals with at least five years old are 96.0% [91.5-99.7]/98.7% [98.1-99.2]--afebrile--and 97.9% [95.3-99.8]/97.7% [96.6-98.6]--febrile. The PCR yields the most reliable results in four subpopulations. CONCLUSIONS: The utility of this RDT in the field seems to be relevant. However, in all subpopulations, data provide enough evidence to suggest caution with the positive predictive values of the RDT. Microscopy has poor sensitivity compared to the other tests, particularly, in the afebrile children less than 5 years. This type of findings reveals the danger of statistical analysis based on microscopy as a reference test. Bayesian Latent Class Models provide a powerful tool to evaluate malaria diagnostic tests, taking into account different groups of interest.
first_indexed 2024-12-23T13:32:55Z
format Article
id doaj.art-767a353d8a674e46b925cc6f33e3d44a
institution Directory Open Access Journal
issn 1932-6203
language English
last_indexed 2024-12-23T13:32:55Z
publishDate 2012-01-01
publisher Public Library of Science (PLoS)
record_format Article
series PLoS ONE
spelling doaj.art-767a353d8a674e46b925cc6f33e3d44a2022-12-21T17:45:07ZengPublic Library of Science (PLoS)PLoS ONE1932-62032012-01-0177e4063310.1371/journal.pone.0040633Bayesian Latent Class Models in malaria diagnosis.Luzia GonçalvesAna SubtilM Rosário de OliveiraVirgílio do RosárioPei-Wen LeeMen-Fang ShaioAIMS: The main focus of this study is to illustrate the importance of the statistical analysis in the evaluation of the accuracy of malaria diagnostic tests, without admitting a reference test, exploring a dataset (n=3317) collected in São Tomé and Príncipe. METHODS: Bayesian Latent Class Models (without and with constraints) are used to estimate the malaria infection prevalence, together with sensitivities, specificities, and predictive values of three diagnostic tests (RDT, Microscopy and PCR), in four subpopulations simultaneously based on a stratified analysis by age groups (< 5, ≥ 5 years old) and fever status (febrile, afebrile). RESULTS: In the afebrile individuals with at least five years old, the posterior mean of the malaria infection prevalence is 3.2% with a highest posterior density interval of [2.3-4.1]. The other three subpopulations (febrile ≥ 5 years, afebrile or febrile children less than 5 years) present a higher prevalence around 10.3% [8.8-11.7]. In afebrile children under-five years old, the sensitivity of microscopy is 50.5% [37.7-63.2]. In children under-five, the estimated sensitivities/specificities of RDT are 95.4% [90.3-99.5]/93.8% [91.6-96.0]--afebrile--and 94.1% [87.5-99.4]/97.5% [95.5-99.3]--febrile. In individuals with at least five years old are 96.0% [91.5-99.7]/98.7% [98.1-99.2]--afebrile--and 97.9% [95.3-99.8]/97.7% [96.6-98.6]--febrile. The PCR yields the most reliable results in four subpopulations. CONCLUSIONS: The utility of this RDT in the field seems to be relevant. However, in all subpopulations, data provide enough evidence to suggest caution with the positive predictive values of the RDT. Microscopy has poor sensitivity compared to the other tests, particularly, in the afebrile children less than 5 years. This type of findings reveals the danger of statistical analysis based on microscopy as a reference test. Bayesian Latent Class Models provide a powerful tool to evaluate malaria diagnostic tests, taking into account different groups of interest.http://europepmc.org/articles/PMC3402519?pdf=render
spellingShingle Luzia Gonçalves
Ana Subtil
M Rosário de Oliveira
Virgílio do Rosário
Pei-Wen Lee
Men-Fang Shaio
Bayesian Latent Class Models in malaria diagnosis.
PLoS ONE
title Bayesian Latent Class Models in malaria diagnosis.
title_full Bayesian Latent Class Models in malaria diagnosis.
title_fullStr Bayesian Latent Class Models in malaria diagnosis.
title_full_unstemmed Bayesian Latent Class Models in malaria diagnosis.
title_short Bayesian Latent Class Models in malaria diagnosis.
title_sort bayesian latent class models in malaria diagnosis
url http://europepmc.org/articles/PMC3402519?pdf=render
work_keys_str_mv AT luziagoncalves bayesianlatentclassmodelsinmalariadiagnosis
AT anasubtil bayesianlatentclassmodelsinmalariadiagnosis
AT mrosariodeoliveira bayesianlatentclassmodelsinmalariadiagnosis
AT virgiliodorosario bayesianlatentclassmodelsinmalariadiagnosis
AT peiwenlee bayesianlatentclassmodelsinmalariadiagnosis
AT menfangshaio bayesianlatentclassmodelsinmalariadiagnosis