Supplementary Material for: The Broad-Spectrum Impact of Hidradenitis Suppurativa on Quality of Life: A Comparison with Psoriasis F.Sampogna L.Fania C.Mazzanti A.Caggiati S.Pallotta A.Panebianco S.Mastroeni B.Didona G.Pintori D.Abeni 2019 <b><i>Background/Aim:</i></b> Hidradenitis suppurativa (HS) is a chronic skin disease with a heavy impact on patients’ quality of life (QoL). The aim of this study was to evaluate in detail the QoL impact of HS comparing it with other skin conditions, and in particular with psoriasis. <b><i>Methods:</i></b> Patients with a diagnosis of HS were recruited. QoL was measured using the Skindex-17 questionnaire. <b><i>Results:</i></b> Data were available for 69 HS patients. HS had the worst QoL among several skin conditions. Compared to psoriasis the mean symptom score was 69.4 versus 53.7, and the mean psychosocial score was 56.1 versus 32.7. Overall, the scores of patients with HS were higher than those of psoriasis patients on 16 of the 17 items of the Skindex-17. <b><i>Conclusions:</i></b> When compared to many different skin conditions, and in particular to psoriasis, HS was the most impairing condition, even at low levels of clinical severity.