Matza, L.S., Brazier, J.E. orcid.org/0000-0001-8645-4780, Stewart, K.D. et al. (8 more authors) (2019) Developing a preference-based utility scoring algorithm for the Psoriasis Area Severity Index (PASI). Journal of Medical Economics, 22 (9). pp. 936-944. ISSN 1369-6998
Abstract
Introduction
It is challenging to identify health state utilities associated with psoriasis because generic preference-based measures may not capture the impact of dermatological symptoms. The Psoriasis Area Severity Index (PASI) is one of the most commonly used psoriasis rating scales in clinical trials. The purpose of this study was to develop a utility scoring algorithm for the PASI.
Methods
Forty health states were developed based on PASI scores of 40 clinical trial patients. Health states were valued in time trade-off interviews with UK general population participants. Regression models were conducted to crosswalk from PASI scores to utilities (e.g., OLS linear, random effects, mean, robust, spline, quadratic).
Results
A total of 245 participants completed utility interviews (51.4% female; mean age =45.3y). Models predicting utility based on the four PASI location scores (head, upper limbs, trunk, lower limbs) had better fit/accuracy (e.g., R2, mean absolute error [MAE]) than models using the PASI total score. Head/upper limb scores were more strongly associated with utility than trunk/lower limb. The recommended model is the OLS linear model based on the four PASI location scores (R2 = 0.13; MAE =0.03). An alternative is recommended for situations when it is necessary to estimate utility based on the PASI total score.
Conclusions
The recommended scoring algorithm may be used to estimate utilities based on PASI scores of any treatment group with psoriasis. Because the PASI is commonly used in psoriasis clinical trials, this scoring algorithm greatly expands options for quantifying treatment outcomes in cost-effectiveness analyses of psoriasis therapies. Results indicate that psoriasis of the head/upper limbs could be more important than trunk/lower limbs, suggesting reconsideration of the standard PASI scoring approach.
Metadata
Item Type: | Article |
---|---|
Authors/Creators: |
|
Copyright, Publisher and Additional Information: | © 2019 Informa UK Ltd. Reproduced in accordance with the publisher's self-archiving policy. |
Keywords: | Health state utilities; Psoriasis Area Severity Index (PASI); psoriasis |
Dates: |
|
Institution: | The University of Sheffield |
Academic Units: | The University of Sheffield > Faculty of Medicine, Dentistry and Health (Sheffield) > School of Health and Related Research (Sheffield) > ScHARR - Sheffield Centre for Health and Related Research |
Depositing User: | Symplectic Sheffield |
Date Deposited: | 17 Jul 2019 10:20 |
Last Modified: | 08 Dec 2021 09:58 |
Status: | Published |
Publisher: | Taylor & Francis |
Refereed: | Yes |
Identification Number: | 10.1080/13696998.2019.1627362 |
Related URLs: | |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:148478 |