Early diagnosis of melanoma

Viewing Exemplars of Melanomas and Benign Mimics of Melanoma Modestly Improves Diagnostic Skills in Comparison with the ABCD Method and Other Image-based Methods for Lay Identification of Melanoma

Ella Cornell1#, Karen Robertson2#, Robert D. McIntosh1 and Jonathan L. Rees2,  Departments of 1Human Cognitive Neuroscience, Psychology and 2Dermatology, University of Edinburgh, UK. #These authors contributed equally to this paper and should be considered as first authors.

Using an experimental task in which lay persons were asked to distinguish between 30 images of melanomas and common mimics of melanoma, we compared various training strategies including the ABC(D) method, use of images of both melanomas and mimics of melanoma, and alternative methods of choosing training image exemplars. Based on a sample size of 976 persons, and an online experimental task, we show that all the positive training approaches increased diagnostic sensitivity when compared with no training, but only the simultaneous use of melanoma and benign exemplars, as chosen by experts, increased specificity and diagnostic accuracy. The ABCD method and use of melanoma exemplar images chosen by laypersons decreased specificity in comparison with the control. The method of choosing exemplar images is important. The levels of change in performance are however very modest, with an increase in accuracy between control and best-performing strategy of only 9%. Key words: skin cancer; melonoma; melanocytic nevi; seborrheic keratosis; diagnosis.