title: An evaluation of direct orthogonal signal correction and other preprocessing methods for the classification of clinical study lots of a dermatological cream.
abstract: Different preprocessing methods (direct orthogonal signal correction (DOSC), standard normal variate (SNV), multiple scatter correction (MSC), first and second derivation, offset correction and detrend correction) are applied to two sets of NIR spectra of a dermatological cream with different concentrations of an active compound. The influence of these preprocessing methods on the classification of the samples into the right concentration class is evaluated using 1 and 3 nearest neighbour method (with Euclidean distance and correlation coefficient as distance parameters) as classification method. PLS and PCR modelling are also used to make a prediction of the concentration of the active compound. The direct orthogonal signal correction gives best results in most of the classification methods.
mesh_terms: D003879:Dermatologic Agents / Q000032:analysis / Q000145:classification*; D004353:Drug Evaluation, Preclinical / Q000379:methods*; D009824:Ointments / Q000032:analysis / Q000145:classification*
chemical_list: D003879:Dermatologic Agents; D009824:Ointments