Table 2.

Comparison of PLS-DA model performance across three different biofluids using leave-one-out-cross-validation to assess performance.

Biofluid	n patients (pos/neg)	p features /after RFECVb	Sensitivity	Specificity	Accuracy a	R2Y	Q2Y
Saliva	47 (23/24)	83/5	0.78	0.83	0.80	0.42	0.26
Sebum	80 (37/43)	998/26	0.92	0.84	0.88	0.63	0.51
Serum	63 (30/33)	472/41	0.97	0.97	0.97	0.90	0.72
Serum (p180 only)	63 (30/33)	86/23	0.83	0.94	0.89	0.78	0.47

^aAll PLS-DA models used 5 components except saliva which found maximum accuracy with 3 components.

^bNumber of features in model is the smaller number after recursive feature elimination with cross-validation.