The substitution of digital images for dermatologic physical examination

Abstract

Objective: To investigate the diagnostic accuracy of clinicians viewing a patient's history and static digital image set compared with clinicians who conducted office-based physical examinations of the same patients.

Design: Observational study.

Setting and patients: One hundred sixteen adult patients presenting with dermatologic symptoms in a university-based practice who consented to have their skin conditions documented with a still digital camera according to a standardized protocol.

Main outcome measures: Concordance between office-based dermatologists' diagnoses and 2 remote clinicians' diagnoses using still digital images (resolution, 92 dots per inch) and identical medical history data to render diagnoses.

Results: When photographic quality was high and office-based clinician certainty was high, remote clinicians were in agreement more than 75% of the time. Office-based and remote clinicians were in agreement 61% to 64% of the time for all cases. No specific disease category appeared to be more or less amenable to diagnosis based on still digital imagery. The diagnostic certainty of the office-based clinician (reported from 0-10) had the most impact on agreement. When cases with office-based clinician certainty of no more than 7 were compared with cases with certainty of at least 9, agreement increased 54% for remote clinician 1 and 111% for remote clinician 2. As an isolated variable, photographic quality had a modest impact on agreement.

Conclusions: Still digital images can substitute for the dermatologic physical examination in up to 83% of cases. This study provides validation of the store-and-forward concept of telemedicine as applied to dermatology. These results serve as the foundation for field testing of the concept in primary care settings.