Estimation of infection prevalence and sensitivity in a stratified two-stage sampling design employing highly specific diagnostic tests when there is no gold standard

Ezer Miller, Amit Huppert, Ilya Novikov, Alon Warburg, Asrat Hailu, Ibrahim Abbasi, Laurence S. Freedman

Research output: Contribution to journalArticlepeer-review

2 Scopus citations

Abstract

In this work, we describe a two-stage sampling design to estimate the infection prevalence in a population. In the first stage, an imperfect diagnostic test was performed on a random sample of the population. In the second stage, a different imperfect test was performed in a stratified random sample of the first sample. To estimate infection prevalence, we assumed conditional independence between the diagnostic tests and develop method of moments estimators based on expectations of the proportions of people with positive and negative results on both tests that are functions of the tests' sensitivity, specificity, and the infection prevalence. A closed-form solution of the estimating equations was obtained assuming a specificity of 100% for both tests. We applied our method to estimate the infection prevalence of visceral leishmaniasis according to two quantitative polymerase chain reaction tests performed on blood samples taken from 4756 patients in northern Ethiopia. The sensitivities of the tests were also estimated, as well as the standard errors of all estimates, using a parametric bootstrap. We also examined the impact of departures from our assumptions of 100% specificity and conditional independence on the estimated prevalence.

Original languageEnglish
Pages (from-to)3349-3361
Number of pages13
JournalStatistics in Medicine
Volume34
Issue number25
DOIs
StatePublished - 10 Nov 2015
Externally publishedYes

Bibliographical note

Publisher Copyright:
Copyright © 2015 John Wiley & Sons, Ltd.

Keywords

  • double sampling
  • prevalence estimation
  • quantitative PCR
  • sensitivity
  • specificity
  • two-stage design

Fingerprint

Dive into the research topics of 'Estimation of infection prevalence and sensitivity in a stratified two-stage sampling design employing highly specific diagnostic tests when there is no gold standard'. Together they form a unique fingerprint.

Cite this