Method for Tongue Feature Analysis through Appropriate Symptom Classification of Various Damjeok Syndrome Phenotypes

Abstract

This study aimed to identify symptom-based pattern clusters of Damjeok syndrome (DS) and verify differences in tongue features across distinct phenotypes, given the multitude of digestive disorders in DS. This clinical study was a prospective and observational study with 904 participants. In the first step, the DS patterns were expected to be determined using the primary categories of DS, and the hierarchical clustering based on participants' symptoms. Subsequently, three groups were divided using a K-means algorithm. Finally, a two-way analysis of variance (adjusted sex, height and weight) and Bonferroni methods were used to examine differences in tongue features among the three groups. The Commission Internationale de l'Éclairage (CIE) L* color value in tongue coating (TC) differed significantly between the A and B groups (P=0.050). Additionally, the TC CIE L* color value in the center area significantly differed between the A and B groups (P = 0.012). Moreover, the TC CIE L* color values in the root area significantly differed between the A and B groups (P = 0.009) and between the A and C groups (P = 0.044), whereas the TC CIE L* color values in the side and tip areas were not significantly different (P=0.149 and 0.360, respectively). No significant differences existed in TC percentage among all groups. These groupings and differences in tongue characteristics can help identify treatment options based on symptoms.