Viewing prior dermopathology diagnoses skews second opinions

Findings from a randomized, controlled trial suggest that for dermatopathologists providing second opinions, reviewing prior diagnoses often sways them to making incorrect diagnoses.

These findings come from a paper published in JAMA Dermatology.

The authors of this study set out to assess whether knowledge of a prior physician’s diagnosis influences consulting physicians’ diagnoses.

To do this, the investigators randomly assigned dermatopathologists to interpret one of five slide sets of 18 melanocytic skin biopsy specimens, in two phases. The five slide sets totalled 90 cases that ranged from class I (benign) to class V (=>pT1b invasive melanoma).

In phase one, the participating physicians conducted their interpretations without any prior diagnostic information. Then after a washout period of at least 12 months, the dermatopathologists interpreted an identical slide deck for phase two. Also in phase two, for a random subset of cases, the participants were shown prior diagnoses by other dermatopathologists that were either more or less severe than their phase one diagnosis of the case.

A total of 149 dermatopathologists participated, with a mean age of 47 years. Of those, 101 were men. They provided 5,322 interpretations of study cases.

The investigators found that the participants were more likely to increase the severity of their diagnosis when the prior diagnosis was of greater severity compared to when no prior diagnosis was provided. Similarly, the participants gave less severe diagnoses to slides if the prior diagnoses were less severe. Prior diagnoses also tended to sway the participants away from correct diagnoses.

These trends were similar among dermatopathologists who earlier said that they were “not at all influenced” 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.”