Cheiloscopy: Lip Print Inter-rater Reliability

Lip print analysis, or cheiloscopy, has the potential to join fingerprints and retinal scans as an additional method to determine human identification. This preliminary study sought to determine agreement among 20 raters, forensic odontologists, using an often referenced system that categorizes lip prints into six classes related to the dominant pattern of vertical, horizontal, and intersecting lines. Lip prints were taken from 13 individuals, and raters categorized eight distinct regions of each print. In addition to ratings made while viewing the actual prints, the raters repeated the exercise using photographs of the lip prints. Multirater kappa, a chance-corrected measure of agreement, ranged between 0.15 for the actual prints and 0.25 for the photos, indicating only poor to fair levels of inter-rater reliability. While these results fail to support the use of lip prints for human identification, it is possible that more intensive training may yet produce adequate levels of reliability.