Comment on “Combining derivative Raman with autofluorescence to improve the diagnosis performance of echinococcosis”

[Display omitted] •PCs shape estimation and cross-validation helps to discard useless PCs.•Probably the autofluorescence do not contains useful information for diagnosis.•Further studies required to determine contributors in specific Raman bands of serum. This paper comments on the article “Combining derivative Raman with autofluorescence to improve the diagnosis performance of echinococcosis” by X. Zheng et al. The authors put forward an idea to apply Raman spectroscopy and autofluorescence to measure spectral characteristics of human serum and diagnose echinococcosis. Despite the high performance of the proposed approach, the demonstrated results may be ambiguous due to the incorrect number of the utilized principal components in classification models for spectral datasets analysis.