Two-stage lot quality assurance sampling framework for monitoring and evaluation of neglected tropical diseases, allowing for imperfect diagnostics and spatial heterogeneity
Fig 7
Impact of geographical variation in prevalence between clusters on program decision-making.
This figure illustrates the impact of the geographical variation in prevalence (expressed as intra-cluster correlation, which ranged from 0.012 to 0.032) on the number of subjects per cluster (nsub; Panel A), the total number of subjects sampled across nclust (ntot; Panel B), the corresponding decision cut-off c (Panel C), and the associated total survey costs (Ctot; Panel D) required for adequate program decision-making (Eovertreat = 25% and Eundertreat = 5%) around a 2% program prevalence threshold. In this figure, the sensitivity and specificity were set at 80% and 98%, respectively. The limits of the grey zone at 1% and 3%. All graphs are based on the same set of 10,000 Monte Carlo simulations.