Development of the Psoriasis Symptoms Scale (PSS) in patients with moderate-to-severe psoriasis: qualitative and quantitative analyses
Background: Psoriasis is a chronic inflammatory skin disease. Objective: To establish content validity and assess psychometric properties of the Psoriasis Symptoms Scale (PSS) in patients with moderate-to-severe psoriasis (Ps). Methods: The PSS is an eight-item patient-completed questionnaire assess...
| Main Authors: | , , , , , , , , |
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| Format: | Article |
| Language: | English |
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Taylor & Francis Group
2020-07-01
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| Series: | Journal of Dermatological Treatment |
| Subjects: | |
| Online Access: | http://dx.doi.org/10.1080/09546634.2019.1623370 |
| _version_ | 1797683661181550592 |
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| author | April W. Armstrong Emily Edson-Heredia April N. Naegeli Russel Burge Jiat-Ling Poon Milena Anatchkova Luna Sun Baojin Zhu Kathleen W. Wyrwich |
| author_facet | April W. Armstrong Emily Edson-Heredia April N. Naegeli Russel Burge Jiat-Ling Poon Milena Anatchkova Luna Sun Baojin Zhu Kathleen W. Wyrwich |
| author_sort | April W. Armstrong |
| collection | DOAJ |
| description | Background: Psoriasis is a chronic inflammatory skin disease. Objective: To establish content validity and assess psychometric properties of the Psoriasis Symptoms Scale (PSS) in patients with moderate-to-severe psoriasis (Ps). Methods: 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 (n = 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 (n = 205). Results: 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 (p < .001). Conclusions: The PSS Symptoms and Signs domains are valid and reliable assessments of patient-reported symptoms and signs, useful for assessing treatment efficacy. |
| first_indexed | 2024-03-12T00:18:05Z |
| format | Article |
| id | doaj.art-57f067a063404671a6534ff99b4b7f69 |
| institution | Directory Open Access Journal |
| issn | 0954-6634 1471-1753 |
| language | English |
| last_indexed | 2024-03-12T00:18:05Z |
| publishDate | 2020-07-01 |
| publisher | Taylor & Francis Group |
| record_format | Article |
| series | Journal of Dermatological Treatment |
| spelling | doaj.art-57f067a063404671a6534ff99b4b7f692023-09-15T14:23:02ZengTaylor & Francis GroupJournal of Dermatological Treatment0954-66341471-17532020-07-0131545245910.1080/09546634.2019.16233701623370Development of the Psoriasis Symptoms Scale (PSS) in patients with moderate-to-severe psoriasis: qualitative and quantitative analysesApril W. Armstrong0Emily Edson-Heredia1April N. Naegeli2Russel Burge3Jiat-Ling Poon4Milena Anatchkova5Luna Sun6Baojin Zhu7Kathleen W. Wyrwich8Keck School of Medicine of USCEli Lilly and CompanyEli Lilly and CompanyEli Lilly and CompanyEvideraEvideraEli Lilly and CompanyEli Lilly and CompanyEli Lilly and CompanyBackground: Psoriasis is a chronic inflammatory skin disease. Objective: To establish content validity and assess psychometric properties of the Psoriasis Symptoms Scale (PSS) in patients with moderate-to-severe psoriasis (Ps). Methods: 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 (n = 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 (n = 205). Results: 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 (p < .001). Conclusions: The PSS Symptoms and Signs domains are valid and reliable assessments of patient-reported symptoms and signs, useful for assessing treatment efficacy.http://dx.doi.org/10.1080/09546634.2019.1623370psoriasispatient-reported outcomessymptomssignspsoriasis symptoms scale |
| spellingShingle | April W. Armstrong Emily Edson-Heredia April N. Naegeli Russel Burge Jiat-Ling Poon Milena Anatchkova Luna Sun Baojin Zhu Kathleen W. Wyrwich Development of the Psoriasis Symptoms Scale (PSS) in patients with moderate-to-severe psoriasis: qualitative and quantitative analyses Journal of Dermatological Treatment psoriasis patient-reported outcomes symptoms signs psoriasis symptoms scale |
| title | Development of the Psoriasis Symptoms Scale (PSS) in patients with moderate-to-severe psoriasis: qualitative and quantitative analyses |
| title_full | Development of the Psoriasis Symptoms Scale (PSS) in patients with moderate-to-severe psoriasis: qualitative and quantitative analyses |
| title_fullStr | Development of the Psoriasis Symptoms Scale (PSS) in patients with moderate-to-severe psoriasis: qualitative and quantitative analyses |
| title_full_unstemmed | Development of the Psoriasis Symptoms Scale (PSS) in patients with moderate-to-severe psoriasis: qualitative and quantitative analyses |
| title_short | Development of the Psoriasis Symptoms Scale (PSS) in patients with moderate-to-severe psoriasis: qualitative and quantitative analyses |
| title_sort | development of the psoriasis symptoms scale pss in patients with moderate to severe psoriasis qualitative and quantitative analyses |
| topic | psoriasis patient-reported outcomes symptoms signs psoriasis symptoms scale |
| url | http://dx.doi.org/10.1080/09546634.2019.1623370 |
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