Physician assistants conduct more skin biopsies, while diagnosing fewer melanomas in situ, compared with dermatologists, according to a study published in JAMA Dermatology.

Alyce M. Anderson, PhD, a medical student at the University of Pittsburgh School of Medicine, and associates conducted a review of medical records to analyze any differences in patient diagnoses among dermatologists and physician assistants.

The investigators collected 33,647 skin cancer examination records from 20,270 individuals (62.8% female, average age, 52.7 years) who were screened from 2011 to 2015 at dermatology offices associated with the University of Pittsburgh Medical Center. The large majority of patients self-reported as non-Hispanic white (96.3%).

Continue Reading

Pathology reports were identified using revision codes V76.43 and Z12.83 from the International Classification of Diseases and International Classification of Diseases and Related Health Problems, respectively. The primary outcome was the number needed to biopsy (NNB) for skin cancer diagnosis (nonmelanoma, invasive melanoma, or in situ melanoma).

NNB per case of skin cancer was 3.9 for diagnosis by physician assistants and 3.3 by dermatologists. For each diagnosed case of melanoma, NNBs were 39.4 and 25.4 for physician assistants and dermatologists, respectively. The researchers noted a significantly less likelihood of melanoma diagnosis in situ for patients diagnosed by physician assistants compared with diagnosis by dermatologists (1.1% vs 1.8%). Variations in diagnoses for invasive melanoma (0.7% vs 0.8%) and nonmelanoma skin cancer (6.1% vs 6.1%) were not significant.

Related Articles

“Visits in which skin cancers are missed and/or biopsies are performed on benign lesions owing to lower diagnostic accuracy are low-value visits and increase the potential harm to patients,” wrote the authors. “This information should be factored into policy decisions about scope of practice, hiring decisions, supervision of APPs, and patient decisions about who provides their dermatologic care.”


Anderson AM, Matsumoto M, Saul MI, Secrest AM, Ferris LK. Accuracy of skin cancer diagnosis by physician assistants compared with dermatologists in a large health care system. [published online April 18, 2018]. JAMA Dermatol. doi:10.1001/jamadermatol.2018.0212