[Preliminary results of DERMATEL: prospective randomized study comparing synchronous and asynchronous modalities of teledermatology].

INTRODUCTION There is considerable variability in the results of studies that evaluate diagnostic reliability in teledermatology. There are only two studies that compare the synchronous and asynchronous modalities of teleconsult in the same sample. We present the results of the pilot project DERMATEL, a study of diagnostic concordance that aims to increase the evidence of these aspects. MATERIAL AND METHODS One-hundred-fifty.nine patients referred by the general practitioner in the first consult were randomized (algorithm 3:2:1) in three arms: asyncronous teledermatology (store-and-forward or SAF), synchronous teldermatology (real-time or VTC), and conventional consult (CC). We used high-quality, fixed digital images in all cases. The patients on the VTC teledermatology arm were also evaluated by videoconference. Finally all patients attended a face-to-face consult, considered the gold standard of patient care. A second dermatologist evaluated the diagnostic and management concordance between the teleconsults and the face-to-face consults. RESULTS One-hundred.forty-seven patients completed the study as follows: 74 in the SAF teledermatology arm, 47 in the VTC teledermatology arm and 26 in the conventional consult (control group). The teledermatological (SAF and VTC) and face-to-face evaluations were identical in 100 of 121 patients (82.6%). The errors were mild in 14 cases (11.6%) and severe in 7 (5.8%). The diagnostic concordance was very high (kappa=0,813). The errors grouped by diseases were as follows: 6/54 (11%) for tumors, 10/30 (33.3%) for inflammatory conditions, 1/20 (5%) for infectious diseases, 3/12 (25%) for alopecia/acne and 1/5 (20%) for others. There were 15 errors in the SAF teledermatology arm (20.3%) and 6 in the VTC teledermatology arm (12.8%); these differences were not statistically significant (chi2 1.12; p=0.288). CONCLUSION The reliability of dermatological teleconsult is very high, especially for tumoral or infectious diseases. The synchronous interaction with audio requires more resources, is difficult to coordinate and its diagnostic efficacy is not superior to SAF teledermatology.