Differences in dermoscopic images from nonpolarized dermoscope and polarized dermoscope influence the diagnostic accuracy and confidence level: a pilot study

Abstract

Background: Studies have demonstrated differences in colors and dermoscopic structures observed with polarized dermoscopes (PDs) and nonpolarized dermoscopes (NPDs).

Objective: The objective was to evaluate whether diagnosis and diagnostic confidence changes when viewing dermoscopic images from NPDs and PDs.

Methods: A total of 100 dermatologists participated in the study. Twenty-five pigmented lesions were shown in the study, consisting of 7 seborrheic keratoses (SK), 3 basal cell carcinomas, 2 atypical nevi, 5 malignant melanomas (MM), 3 dermatofibromas, 3 blue nevi, and 2 hemangiomas. Two images of each lesion (one NPD and one PD) were included. The McNemar test and paired t-test were used for the statistical analysis.

Results: Ninety-one participants completed the study. Significant differences in the diagnoses were observed for the SK, atypical nevus, and MM images. Seventy-five percent and 59% of the final participants correctly diagnosed SK when presented with the NPD and PD images, respectively. For MM, 23 and 34% made the correct diagnoses with the NPD and PD images, respectively.

Conclusions: Viewing lesions with NPD versus PD can affect the diagnosis and diagnostic confidence of physicians that are novices with dermoscopy. Further studies including physicians at different expertise levels and a larger sample of lesions are needed to further explore the differences.