Reliability and validity of Pemphigus Oral Lesions Intensity Score (POLIS) in pemphigus vulgaris

Abstract

Oral involvement in pemphigus vulgaris (PV) may present as the first or sole symptom. The absence of a reliable oral-specific scoring system complicates disease assessment, monitoring, and clinical trials. This study aimed to evaluate the reliability and validity of the Pemphigus Oral Lesions Intensity Score (POLIS) in comparison with the oral section of Pemphigus Disease Area Index (PDAI-oral), alongside completion time and variable correlations. A cross-sectional study was conducted in the clinic of a referral dermatology hospital. Sixty-eight confirmed oral PV patients (female-male ratio, 1.5:1) with an age of 47.29 ± 11.62 and a disease duration of 5.15 ± 4.08 years were enrolled. Two expert dermatologists examined each patient separately and documented the score and completion time of PDAI-oral and POLIS. A follow-up session was conducted for repeated assessment, in which 14 patients participated. Excellent inter-rater reliability was observed for both PDAI-oral (ICC = 0.958) and POLIS (ICC = 0.928). The strong and statistically significant Pearson correlation between these two scoring systems (r = 0.724, p-value < 0.001 for dermatologist No. 1 and r = 0.746, p-value < 0.001 for dermatologist No. 2) demonstrated POLIS validation in our study. However, the required time for completing POLIS was significantly more than PDAI. POLIS may serve as a comprehensive method for assessing oral PV, addressing both clinical severity and patient-reported aspects of the disease.