Figure 4.

Relative bias in cumulative incidence estimation. For each panel, the raw seroprevalence result (p_raw) is shown on the x-axis and the ratio of the estimated cumulative incidence (CI) to raw seroprevalence is shown on the y-axis (median and 95% credible interval; plotted using a log2 scale). The ratio equaling 1 (i.e., no bias) is shown in the dashed horizontal line. All panels are generated under the primary scenario of classifying disease severity into 2 groups, nonhospitalized and hospitalized. A) Italy, where each point represents a region. Spain, where each point represents a province: B) round 1; C) round 2. The 9 census divisions of the United States, where the shape of the point represents the survey round (legend provided in panel D): D) East North Central, E) East South Central, F) Middle Atlantic, G) Mountain, H) New England, I) Pacific, J) South Atlantic and Puerto Rico, K) West North Central, and L) West South Central. M) Manaus, Brazil, where each point represents a month. For the United States and Manaus, Brazil, the cumulative incidence estimates are weighted by population demography and age-specific disease severity. N) Japan, where each point represents a prefecture. The scenario considered here is the case of using the results of the 2 assays.