The present invention involves the use of fluorescence spectroscopy in the diagnosis of cervical cancer and precancer. Using multiple illumination wavelengths, it is possible to (i) differentiate normal or inflamed tissue from squamous intraepithelial lesions (SILs) and (ii) to differentiate high grade SILs from non-high grade SILs. The detection may be performed in vitro or in vivo. Multivariate statistical analysis was employed to reduce the number of fluorescence excitation-emission wavelength pairs needed to re-develop algorithms that demonstrate a minimum decrease in classification accuracy. Fluorescence at excitation-emission wavelength pairs was used to redevelop and test screening and diagnostic algorithms that have a similar classification accuracy to those that employ fluorescence emission spectra at three excitation wavelengths. Both the full-parameter and reduced-parameter screening algorithms discriminate between SILs and non-SILs with a similar specificity and a substantially improved sensitivity relative to Pap smear screening and differentiate high grade SILs from non-high grade SILs.