Label-free imaging and classification of live P. falciparum enables high performance parasitemia quantification without fixation or staining
Fig 3
Analysis of classification statistics vs. focal offset in deep UV images acquired at 285 nm.
In all panels, solid lines refer to statistics from processing all cells at the same global focus offset, while dashed lines correspond to using the optimal focus slice on a cell-by-cell basis, determined via the maximum confidence strategy. a) False positive rate vs. defocus from global optimum for all three parasite stages, b) Recall vs. defocus for all categories, c) Precision vs. defocus, d) Overall accuracy vs. defocus, and e) Sample composition estimation error vs. defocus. f) Histogram showing frequency of slice usage in the max confidence method. Slice number 3 is the global best focus slice, with slices evenly spaced in 0.5 μ increments. g) Resulting improved confusion matrix after applying the max confidence method. To increase the number of datapoints, all focus-dependent dataset statistics in this figure and its supplementary figures were derived from analyzing pooled classifier training and validation datasets as a function of focus slice.