Am J Epidemiol. 2023 Nov 3:kwad212. doi: 10.1093/aje/kwad212. Online ahead of print.
ABSTRACT
In a recent systematic review, Bastos et al. compared the sensitivities of saliva sampling and nasopharyngeal swabs in the detection of SARS-CoV-2 infection by assuming a composite reference standard defined as positive if either test is positive, and negative if both tests are negative (double negative). Even under a perfect specificity assumption, this approach ignores the double-negative results and risks overestimating the sensitivities due to residual misclassification. In this article, we first illustrate the impact of double-negative results in the estimation of the sensitivities in a single study, and then propose a two-step latent class meta-analysis method to re-evaluate both sensitivities using the same published dataset in Bastos et al. by properly including the observed double-negative results. We also conduct extensive simulation studies to compare the performance of the proposed method and Bastos et al.’s method for varied levels of prevalence and between-study heterogeneity. The results demonstrate that the sensitivities are overestimated noticeably in Bastos et al.’s method, and the proposed method provides a more accurate evaluation with nearly no bias and close to nominal coverage probability. In conclusion, double-negative results can significantly impact the estimated sensitivities when a gold standard is absent, and thus should be properly incorporated.
PMID:37939113 | DOI:10.1093/aje/kwad212
