摘要:
Methods and apparatus for estimating and removing spectral interference improve precision and robustness of non-invasive analyte measurement using Near-infrared (NIR) spectroscopy. The estimation of spectral interference is accomplished, either through multivariate modeling or discrete factor analysis, using a calibration set of samples in which the interference is orthogonal to the analyte signal of interest, or where the shape of the interference is known. Each of the methods results in a multivariate model in which the spectral interference is estimated for a new sample and removed by vector subtraction. Independent models based on classes of sample variability are used to collapse spectral interference and determine more accurately which model is best equipped to estimate the signal of interference in the new sample. Principal components analysis and other commonly known analytical techniques can be used to determine class membership.