Figure 3.
Consequences of correcting seroprevalence estimates using biased estimates of sensitivity (Sn.) and specificity (Sp.): simulation-based analysis. Serological assay with (a) high: a true Sn. at 95.0% and a true Sp. at 99.0%, (b) good: a true Sn. at 90.0% and a true Sp. at 97.0%, (c) and moderate performance: a true Sn. at 80.0% and a true Sp. at 87.0%. Note: The dot–dash lines provide an interval which indicates the seroprevalence adjusted for the mis-specified assay performance at a given error level was still within ±5% deviation of the true seroprevalence. The prevalence adjustment was performed using the formula by Sempos and Tian [20]. Notice that an assay with underestimated Sn. and Sp. is unable to provide prevalence estimates after adjustment at a low prevalence setting: (a) 5.3% and (b) 5.6%. An assay with overestimated Sn. and Sp. tends to inflate seroprevalence after adjustment when the true prevalence is low: (b) 3.0%.
