Table 3. Sensitivity (sens.), specificity (spec.), positive predictive value (PPV) and area under the receiver operating curve (AUC) for decision tree models to discriminate between dengue fever (DF) or dengue hemorrhagic fever (DHF) versus chikungunya, using data at presentation.

Model	Suitable for less resourced settings?	Sens. detect DF/DHF	Spec. detect DF/DHF	PPV detect DF/DHF	Sens. detect chikungunya	Spec. detect chikungunya	PPV detect chikungunya	AUC
chikungunya vs DF	Yes	0.95	0.36	0.84	0.36	0.95	0.64	0.59
chikungunya vs DF	No	0.99	0.52	0.88	0.52	0.99	0.95	0.91
chikungunya vs DHF	Yes	0.95	0.90	0.76	0.90	0.95	0.98	0.91
chikungunya vs DHF	No	0.93	1.00	1.00	1.00	0.93	0.97	0.99