Randomized controlled trial comparing store-and-forward teledermatology alone and in combination with web-camera...

Studies on the reliability of teledermatology have shown considerable variability in results. Only one study has compared asynchronous and synchronous methods.

This report describes DERMATEL, a prospective, randomized diagnostic-concordance study that sought to evaluate the relative advantages, in terms of reliability, of two remote consultation techniques.

Patients referred by 18 general practitioners were randomized (4 : 4 : 2) to three study groups: store and forward (SF), hybrid videoconferencing-SF (VC-SF), and a control group. In total, 457 patients were assigned: 192 to the SF group, 176 to the VC-SF group and 89 to the control group. High-quality still images were used throughout, with additional use of standard web-camera (webcam) videoconferencing in the VC-SF group. All patients were also seen by the same dermatologist in a face-to-face (FTF) consultation, considered the practical reference standard. Two different dermatologists assessed concordances between the teledermatology and FTF consultations.

There were no significant differences in age, gender or diagnostic category between the three groups, and the images (82%), clinical history (91%) and diagnostic confidence (89%) were high-quality. Online management was possible for 70% of cases. Agreement between teledermatology and the FTF consultation was high for both diagnosis (> 0.85) and treatment (> 0.78). Concordance in diagnosis was influenced by image quality (P < 0.001), confidence in diagnosis (P < 0.001) and need for conventional consultation (P < 0.001), rather than by quality of clinical history (P = 0.58) or method of teleconsultation (P = 0.340).

Intraobserver reliability is very high in teledermatology. When history taking and training in digital photography are standardised, a hybrid system with audio is no better than SF alone.