Department of Statistics, Corvinus University of Budapest, 8 Fővám tér, 1093, Budapest, Hungary.
Doctoral School of Psychology, Institute of Psychology, Eötvös Loránd University, 46 Izabella u., 1064, Budapest, Hungary.
Health Qual Life Outcomes. 2022 Jun 3;20(1):87. doi: 10.1186/s12955-022-01995-x.
Dermatology Life Quality Index (DLQI) scores are used in many countries as access and reimbursement criteria for costly dermatological treatments. In this study we examined how time trade-off (TTO) utility valuations made by individuals from the general population are related to combinations of DLQI severity levels characterizing dermatologically relevant health states, with the ultimate purpose of developing a value set for the DLQI.
We used data from an online cross-sectional survey conducted in Hungary in 2020 (n = 842 after sample exclusions). Respondents were assigned to one of 18 random blocks and were asked to provide 10-year TTO valuations for the corresponding five hypothetical health states. To analyze the relationship between DLQI severity levels and utility valuations, we estimated linear, censored, ordinal, and beta regression models, complemented by two-part scalable models accommodating heterogeneity effects in respondents' valuation scale usage. Successive severity levels (0-3) of each DLQI item were represented by dummy variables. We used cross-validation methods to reduce the initial set of 30 dummy variables and improve model robustness.
Our final, censored linear regression model with 13 dummy variables had R = 0.136, thus accounting for 36.9% of the incremental explanatory power of a maximal (full-information) benchmark model (R = 0.148) over the uni-dimensional model (R = 0.129). Each DLQI item was found to have a negative effect on the valuation of health states, yet this effect was largely heterogeneous across DLQI items, and the relative contribution of distinctive severity levels also varied substantially. Overall, we found that the social/interpersonal consequences of skin conditions (in the areas of social and leisure activities, work and school, close personal relationships, and sexuality) had roughly twice as large disutility impact as the physical/practical aspects.
We have developed an experimental value set for the DLQI, which could prospectively be used for quantifying the quality-adjusted life years impact of dermatological treatments and serve as a basis for cost-effectiveness analyses. We suggest that, after validation of our main results through confirmatory studies, population-specific DLQI value sets could be developed and used for conducting cost-effectiveness analyses and developing financing guidelines in dermatological care.
皮肤病生活质量指数（DLQI）评分被许多国家用作昂贵皮肤病治疗的准入和报销标准。本研究旨在探讨一般人群的时间权衡（TTO）效用评估与描述皮肤病相关健康状况的 DLQI 严重程度水平的组合之间的关系，最终目的是为 DLQI 制定一个价值体系。
我们使用了 2020 年在匈牙利进行的一项在线横断面调查的数据（经样本排除后为 842 名参与者）。受访者被分配到 18 个随机块中的一个，并被要求对相应的 5 个假设健康状态提供 10 年 TTO 估值。为了分析 DLQI 严重程度水平与效用评估之间的关系，我们估计了线性、删失、有序和贝塔回归模型，并补充了两部分可扩展模型，以适应受访者估值量表使用中的异质性效应。每个 DLQI 项目的连续严重程度（0-3）由虚拟变量表示。我们使用交叉验证方法来减少初始的 30 个虚拟变量集，并提高模型的稳健性。
我们最终的删失线性回归模型有 13 个虚拟变量，R²为 0.136，因此比最大（完全信息）基准模型（R²为 0.148）对单一维度模型（R²为 0.129）的增量解释能力高出 36.9%。每个 DLQI 项目都对健康状态的估值产生负面影响，但这种影响在 DLQI 项目之间存在很大的异质性，不同特征严重程度的相对贡献也有很大差异。总的来说，我们发现皮肤状况的社会/人际关系后果（社交和休闲活动、工作和学校、亲密人际关系和性）的不舒适影响大约是身体/实际方面的两倍。
我们已经为 DLQI 制定了一个实验价值体系，该体系可用于前瞻性地量化皮肤病治疗的质量调整生命年影响，并作为成本效益分析的基础。我们建议，在通过验证性研究验证我们的主要结果后，可以开发针对特定人群的 DLQI 价值体系，并将其用于进行成本效益分析和制定皮肤病护理的融资指南。
