Table 2.

Regression model performance based on FFNN and RReliefF-SOM for HbA1c and glucose in vivo quantification. The spectral interval between 200 and 1800 cm⁻¹ was used to select the mentioned features

	Body region	Forearm	Wrist	Index finger
HbA1c	# Features	100	512	50
	# k-nearest neighbors	13	26	23
	RMSE-CV (HbA1c %) ± SD	1.00 ± 0.08	0.69 ± 0.07	1.52 ± 0.41
Glucose	# Features	200	150	150
	# k-nearest neighbors	9	7	38
	RMSE-CV (glucose mg/dL) ± SD	30.12 ± 0.53	41.44 ± 4.68	49.67 ± 1.66