[Store-and-forward teledermatology: assessment of validity in a series of 2000 observations]

Abstract

Background and objectives: The aim of this study was to assess the validity of store-and-forward teledermatology as a tool to support physicians in primary care and hospital emergency services and reduce the requirement for face-to-face appointments. Diagnostic validity and the approach chosen for patient management (face-to-face vs teledermatology) were compared according to patient origin and diagnostic group.

Material and methods: Digital images from 100 patients were assessed by 20 different dermatologists and the diagnoses offered were compared with those provided in face-to-face appointments (gold standard). The proposed management of the different groups of patients was also compared.

Results: The percentage complete agreement was 69.05% (95% confidence interval [CI], 66.9%-71.0%). The aggregate agreement was 87.80% (95% CI, 86.1%-89.0%). When questioned about appropriate management of the patients, observers elected face-to-face consultation in 60% of patients (95% CI, 58%-61%) and teledermatology in 40% (95% CI, 38%-41%). Diagnostic validity was higher in patients from primary care (76.1% complete agreement and 91.8% aggregate agreement) than those from hospital emergency services (61.8% complete agreement, 83.4% aggregate agreement) (p < 0.001) and teledermatology was also chosen more often in patients from primary care compared with those from emergency services (42% vs 38%; p=0.003). In terms of diagnostic group, higher validity was observed for patients with infectious diseases (73.3% complete agreement and 91.3% aggregate agreement) compared to those with inflammatory disease (70.8% complete agreement and 86.4% aggregate agreement) or tumors (63.0% complete agreement and 87.2% aggregate agreement) (p <0.001). Teledermatology was also chosen more often in patients with infectious diseases (52%) than in those with inflammatory disease (40%) or tumors (28%) (p <0.001).

Conclusions: Store-and-forward teledermatology has a high level of diagnostic validity, particularly in those cases referred from primary care and in infectious diseases. It can be considered useful for the diagnosis and management of patients at a distance and would reduce the requirement for face-to-face consultation by 40%.