Estimation of SARS-CoV-2 Seroprevalence in Central North Carolina: Accounting for Outcome Misclassification in Complex Sample Designs

Citation

Vias, Nishma P.; Cassidy, Caitlin A.; Edwards, Jessie K.; Xiong, Khou; Beatty Parker, Cherese; Aiello, Allison E.; Boyce, Ross M.; & Shook-Sa, Bonnie E. (2023). Estimation of SARS-CoV-2 Seroprevalence in Central North Carolina: Accounting for Outcome Misclassification in Complex Sample Designs. Epidemiology, 34(5), 721-731. PMCID: PMC10403265

Abstract

BACKGROUND: Population-based seroprevalence studies are crucial to understand community transmission of COVID-19 and guide responses to the pandemic. Seroprevalence is typically measured from diagnostic tests with imperfect sensitivity and specificity. Failing to account for measurement error can lead to biased estimates of seroprevalence. Methods to adjust seroprevalence estimates for the sensitivity and specificity of the diagnostic test have largely focused on estimation in the context of convenience sampling. Many existing methods are inappropriate when data are collected using a complex sample design.
METHODS: We present methods for seroprevalence point estimation and confidence interval construction that account for imperfect test performance for use with complex sample data. We apply these methods to data from the Chatham County COVID-19 Cohort (C4), a longitudinal seroprevalence study conducted in central North Carolina. Using simulations, we evaluate bias and confidence interval coverage for the proposed estimator compared with a standard estimator under a stratified, three-stage cluster sample design.
RESULTS: We obtained estimates of seroprevalence and corresponding confidence intervals for the C4 study. SARS-CoV-2 seroprevalence increased rapidly from 10.4% in January to 95.6% in July 2021 in Chatham County, North Carolina. In simulation, the proposed estimator demonstrates desirable confidence interval coverage and minimal bias under a wide range of scenarios.
CONCLUSION: We propose a straightforward method for producing valid estimates and confidence intervals when data are based on a complex sample design. The method can be applied to estimate the prevalence of other infections when estimates of test sensitivity and specificity are available.

URL

http://dx.doi.org/10.1097/EDE.0000000000001625

Reference Type

Journal Article

Year Published

2023

Journal Title

Epidemiology

Author(s)

Vias, Nishma P.
Cassidy, Caitlin A.
Edwards, Jessie K.
Xiong, Khou
Beatty Parker, Cherese
Aiello, Allison E.
Boyce, Ross M.
Shook-Sa, Bonnie E.

Article Type

Regular

PMCID

PMC10403265

Data Set/Study

Chatham County COVID-19 Cohort (C4)

Continent/Country

United States

State

North Carolina

Race/Ethnicity

Black
White

ORCiD

Boyce, R - 0000-0002-9489-6324
Edwards, J -0000-0002-1741-335X