Objective: To evaluate whether the differences in colors and structures observed in dermoscopic images from non-polarized dermoscopes (NPD) and polarized dermoscopes (PD) can impact physicians' diagnostic ability and their confidence levels.Participants: 100 dermatologists who attended a one-day course on the fundamental of dermoscopy course at Memorial Sloan-Kettering Cancer Center.Design: Twenty five pigmented lesions were chosen, which consisted of 7 seborrheic keratoses, 3 basal cell carcinomas, 2 atypical nevi, 5 melanomas, 3 dermatofibromas, 3 blue nevi and 2 hemangiomas. Two images of each lesion (one NPD and one PD) for a total of 50 lesions were included in the image presentation. Participants were not informed of the study design and were not told that they would be viewing the same lesions under 2 different imaging modalities. Statistical analysis examining the participants' responses was performed using the McNemar's test and Paired t test.Main Outcome Measures: The main outcomes included the assessment of the diagnostic accuracy and confidence level for clinicians viewing lesions via NPD and PD.Results: Ninty-one participants completed the study. Statistically significant differences in the diagnoses were observed in the seborrheic keratosis, atypical nevus and melanoma groups. For seborrehic keratosis, 75% and 59% of the final participants correctly diagnosed SK when presented with the NPD and PD images, respectively. For atypical nevi, 19% and 33% had the correct diagnoses when presented with NPD and PD images, respectively. For melanomas, 23% and 34% had correct diagnoses with the NPD and PD images, respectively. For the categories of seborrehic keratosis and atypical nevus, participants were statistically more confident in their diagnoses when presented with the NPD images than with the PD images. For the category of basal cell carcinoma, participants were more confident in their diagnosis when viewing the PD images compared to the NPD images.Conclusion: There are observed differences between NPD and PD in term of the color and structure visualized. In some cases, physicians diagnostic accuracy and confidence are affected by the differences seen with the different dermoscopes. NPD and PD appears to provide different but complementary information.