Rapid determination of preliminary thalassaemia screening indicators based on near-infrared spectroscopy with wavelength selection stability

Abstract

A rapid determination method for the preliminary thalassaemia screening indicators—haemoglobin (Hb), mean corpuscular Hb (MCH) and mean corpuscular volume (MCV)—based on near-infrared (NIR) spectroscopy was developed. Wavelength selections were accomplished using the improved moving window partial least squares (MWPLS) method for stability. Each model was established using an approach based on randomness, similarity and stability to obtain objective, stable and practical models. The optimal wavebands screened using MWPLS were 1538 nm to 1756 nm for Hb and 968 nm to 1028 nm for MCH and MCV, which were within the NIR overtone region. The validation root mean square error, validation correlation coefficients and relative validation root mean square error of prediction were 3.9 g L⁻¹, 0.972 and 2.9% for Hb; 1.41 pg, 0.958 and 4.8% for MCH; and 4.09 fL, 0.929 and 4.9% for MCV, respectively. The three models achieved high validation accuracy, and the Hb, MCH and MCV prediction values were close to the clinical measured values. Based on the cut-off values (MCH = 27.0 pg, MCV = 80.0 fL) for the routine method, the sensitivity and specificity both reached 100% based on the spectral-predicted MCH and MCV values in the validation set. The spectral prediction was highly accurate for determining negative and positive samples in preliminary thalassaemia screening. The proposed method is rapid and simple compared with the conventional method. This technique is a promising tool for preliminary thalassaemia screening in population prevention and control programmes. This study provides valuable references for designing specialised spectrometers.