To the Editor To reduce the costs of treating skin cancer, Shahwan and Kimball1 suggest restricting the performance of biopsies for skin cancer to clinicians with favorable number-needed-to-biopsy (NNB) ratios. However, when viewed in isolation, the NNB is a limited surrogate for diagnostic accuracy and a problematic metric for assessing cost-effectiveness.
Marchetti MA, Dusza SW, Halpern AC. A Closer Inspection of the Number Needed to Biopsy. JAMA Dermatol. 2016;152(8):952-953. doi:10.1001/jamadermatol.2016.0936