Tehran University of Medical Sciences Acta Medica Iranica 0044-6025 51 4 2013 04 15 224 230 EN Cheyda Chams-Davatchi Autoimmune Bullous Diseases Research Center, Tehran University of Medical Sciences, Tehran, Iran. Ziba Rahbar Autoimmune Bullous Diseases Research Center, Tehran University of Medical Sciences, Tehran, Iran. Maryam Daneshpazhooh Autoimmune Bullous Diseases Research Center, Tehran University of Medical Sciences, Tehran, Iran. Seyed Mohammad Ali Mortazavizadeh Autoimmune Bullous Diseases Research Center, Tehran University of Medical Sciences, Tehran, Iran. Maryam Akhyani Autoimmune Bullous Diseases Research Center, Tehran University of Medical Sciences, Tehran, Iran. Nafiseh Esmaili Autoimmune Bullous Diseases Research Center, Tehran University of Medical Sciences, Tehran, Iran. Kamran Balighi Autoimmune Bullous Diseases Research Center, Tehran University of Medical Sciences, Tehran, Iran. 2015 10 11 Pemphigus is a rare autoimmune blistering disease with different phenotypes. The evaluation of therapeutic interventions requires a reliable, valid and feasible to use measurement. However, there is no gold standard to measure the disease activity in clinical trials. In this study we aimed to introduce the pemphigus vulgaris activity score (PVAS) measurement and to assess the convergent validity with the experts' opinion of disease activity. In PVAS scoring, the distribution of pemphigus vulgaris antigen expression in different anatomical regions is taking in to account with special consideration of the healing process. PVAS is a 0-18 scale, based on the extent of mucocutaneous involvement, type of lesion and the presence of Nikolsky's sign. The sum of the scores of total number of lesions, number of different anatomic regions involvement and Nikolsky's sign is weighted by the type of lesion. In the present study, PVAS was assessed in 50 patients diagnosed with pemphigus vulgaris by one dermatologist. Independently, five blinded experts scored all the patients through physician's global assessment (PGA). The convergent validity with experts' opinion was assessed. The Spearman coefficient of correlation showed the acceptable value of 0.751 (95%CI: 0.534- 0.876). PVAS is a valid, objective and simple-to-use scoring measurement. It showed a good correlation with PGA of pemphigus disease activity in Iranian patients with pemphigus vulgaris. https://acta.tums.ac.ir/index.php/acta/article/view/4458 https://acta.tums.ac.ir/index.php/acta/article/download/4458/4521