Prior diagnoses influence dermatopathologists’ interpretations

When interpreting melanocytic skin biopsy specimens, knowledge of a prior diagnosis sways dermatopathologists to make more and less severe diagnoses and can also sway them from a correct to an incorrect diagnosis

Joann G. Elmore, M.D., from the University of California in Los Angeles, and colleagues measured the extent to which dermatopathologists’ diagnoses are influenced by prior diagnostic information from another dermatopathologist. The analysis included 149 dermatopathologists providing 5,322 interpretations of study cases.

The researchers found that participants were more likely to increase the severity of their diagnosis when the prior diagnosis was of greater severity versus interpretations with no prior diagnosis provided. Similarly, participants gave less severe diagnoses when prior diagnoses were of lesser severity. Findings were similar even among dermatopathologists who had reported they were “not at all influenced” by prior diagnoses. Dermatopathologists were swayed away from correct diagnoses by prior diagnoses.

“In this randomized controlled trial, despite the preference of most dermatopathologists to receive prior diagnoses when providing second opinions, this information swayed them away from a correct diagnosis to an incorrect diagnosis,” the authors write. “Dermatopathologists providing second opinions should be blinded to first opinions if the goal is to obtain an independent diagnostic opinion.”