International validation of the Bullous Pemphigoid Disease Area Index severity score and calculation of cut‐off values for defining mild, moderate and severe types of bullous pemphigoid. - Masmoudi, W.; Vaillant, M.; Vassileva, S.; Patsatsi, A.; Quereux, G.; Moltrasio, C.; Abasq, C.; Prost‐Squarcioni, C.; Kottler, D.; Kiritsi, D.; Litrowski, N.; Plantin, P.; et al. (British Journal of Dermatology, 2021)