Beyond Psoriasis Area and Severity Index and Body Surface Area: An Italian Delphi Consensus on the Definition of Moderate Psoriasis

Introduction: Moderate psoriasis, despite its clinical relevance, remains inconsistently defined in current guidelines, leading to heterogeneous treatment decisions and variable access to systemic therapy. A unified, clinically meaningful definition is currently lacking. To establish a consensus-based, operational definition of moderate psoriasis, we conducted a two-round modified Delphi process involving expert dermatologists. Methods: Fifteen Italian dermatologists with recognized expertise in psoriasis participated in a Delphi survey composed of 18 statements addressing clinical severity, quality of life, symptoms, involvement of special areas, and treatment response. Consensus was defined as a median score ≥ 7 with interquartile range (IQR) ≤ 2, or ≥ 75% of ratings ≥ 7, on a scale going from 1 (completely disagree) to 10 (completely agree). Statements not reaching consensus in Round 1 were revised according to participants' comments and re-evaluated in Round 2. Results: In Round 1, 12 of 18 statements reached consensus. Six statements required revision owing to ambiguity or insufficient operational clarity. After refinement, including clearer definitions of early and frequent relapses, specification of Dermatology Life Quality Index (DLQI) thresholds, and explicit mention of difficult-to-treat or highly visible areas, all six statements achieved consensus in Round 2. Ultimately, consensus was obtained for all 18 statements. Conclusions: This Delphi process produced a comprehensive and clinically actionable definition of moderate psoriasis, emphasizing a multidimensional view of severity that extends beyond Psoriasis Area and Severity Index (PASI) or Body Surface Area (BSA). These consensus-based criteria may support earlier access to systemic therapies, including biologics and small molecules, and improve harmonization in both clinical practice and research.