Armstrong April W, Edson-Heredia Emily, Naegeli April N, Burge Russel, Poon Jiat-Ling, Anatchkova Milena, Sun Luna, Zhu Baojin, Wyrwich Kathleen W
Department of Dermatology, Keck School of Medicine of USC, Los Angeles, CA, USA.
Eli Lilly and Company, Indianapolis, IN, USA.
J Dermatolog Treat. 2020 Aug;31(5):452-459. doi: 10.1080/09546634.2019.1623370. Epub 2019 Jul 15.
Psoriasis is a chronic inflammatory skin disease. To establish content validity and assess psychometric properties of the Psoriasis Symptoms Scale (PSS) in patients with moderate-to-severe psoriasis (Ps). The PSS is an eight-item patient-completed questionnaire assessing symptoms (itch, pain, stinging, burning), signs (redness, scaling, cracking), and discomfort. Content validity was established during interviews of patients ( = 14) with Ps. PSS Symptoms and Signs domain scores were evaluated for reliability, construct validity, and responsiveness using data from a clinical study (NCT02899988) in Ps ( = 205). Patients confirmed content validity; the PSS was understandable and relevant. Cronbach's alphas were 0.84 (Symptoms) and 0.86 (Signs), demonstrating internal consistency reliability. Test-retest reliability was confirmed in patients before receiving study drug (intraclass coefficient: 0.82 [Symptoms]; 0.81 [Signs]). Convergent and discriminant validity were demonstrated at baseline and Week 16 by large (≥0.50) correlations between PSS Symptoms and Signs domain scores and Dermatology Life Quality Index total and symptoms and feelings domain scores, and small (<0.30) correlations with Short Form-36 Mental Component Summary score, respectively. Symptoms and Signs scores responded to clinical changes ( < .001). The PSS Symptoms and Signs domains are valid and reliable assessments of patient-reported symptoms and signs, useful for assessing treatment efficacy.
银屑病是一种慢性炎症性皮肤病。旨在确立中度至重度银屑病（Ps）患者中银屑病症状量表（PSS）的内容效度并评估其心理测量学特性。PSS是一份由患者自行填写的包含八个条目的问卷，用于评估症状（瘙痒、疼痛、刺痛、灼痛）、体征（发红、脱屑、皲裂）及不适情况。通过对14例Ps患者进行访谈确立了内容效度。利用一项Ps临床研究（NCT02899988）中的数据（n = 205），对PSS症状和体征领域得分进行了可靠性、结构效度和反应度评估。患者确认了内容效度；PSS易于理解且相关。Cronbach's α系数在症状方面为0.84，体征方面为0.86，表明具有内部一致性可靠性。在接受研究药物前的患者中证实了重测可靠性（组内相关系数：症状方面为0.82；体征方面为0.81）。在基线和第16周时，PSS症状和体征领域得分与皮肤病生活质量指数总分、症状及感受领域得分之间具有较大相关性（≥0.50），而与简明健康状况调查简表精神成分总结得分之间具有较小相关性（<0.30），分别证明了收敛效度和区分效度。症状和体征得分对临床变化有反应（P <.001）。PSS症状和体征领域是对患者报告的症状和体征的有效且可靠的评估，有助于评估治疗效果。
