Method-specific thresholds and the corresponding probabilities of classifying moderate-to-heavy and light intensity infections.
The method-specific thresholds were derived from receiver operating (ROC) curves for Mini-FLOTAC, FECPAKG2, McMaster and qPCR, separately. In these ROC analyses, the reference classification of moderate-to-heavy intensity (M&HI) infections was based on the Kato-Katz and the World Health Organization infection intensity thresholds (Table 1). They maximize the percentage of correctly classified M&HI infections while minimizing the percentage of light intensity infections falsely classified as M&H. The thresholds are expressed as eggs per gram of stool (EPG) for Mini-FLOTAC, FECPAKG2 and McMaster, and as the number of genome equivalents per ml of DNA (GE/ml) for qPCR. The Kappa reflects the degree of agreement in classifying M&HI infections based on the method-specific thresholds between the microscopic methods (Mini-FLOTAC, FECPAKG2 and McMaster) and the reference method (Kato-Katz and WHO thresholds). 95% CI: 95% confidence interval; M&H: moderate-to-heavy.