Zug K A, Littenberg B, Baughman R D, Kneeland T, Nease R F, Sumner W, O'Connor G T, Jones R, Morrison E, Cimis R
Department of Medicine, Dartmouth-Hitchcock Medical Center, Lebanon, NH, USA.
Arch Dermatol. 1995 May;131(5):561-8.
Patient preferences for health outcomes can be explicitly assessed and expressed in quantitative terms known as utilities. Three standard methods for utility assessment have been used to quantify patient preferences, but these methods have not previously been applied to skin disease. Eighty-seven patients with psoriasis from a tertiary medical center were interviewed, using an interactive, computer-based utility assessment questionnaire, U-Titer. Utilities for three categories of psoriasis severity and potential adverse outcomes of methotrexate therapy were assessed by the vertical rating scale, time trade-off, and standard gamble.
Patients assigned a broad range of utilities for each of the health states. Utilities obtained by the vertical rating scale did not correlate well with utilities obtained by standard gamble or time trade-off methods. However, utilities assessed by standard gamble and time trade-off were not significantly different. Patient characteristics such as age, gender, and education were not correlated with utility and did not explain the variation. Indicators of the patients' disease severity were not predictive of utilities for the assessed health states. The relatively high utility for liver biopsy suggests that there is less patient aversion to the procedure than suspected.
Utilities, or quantitative measures of patient preferences for health states, are measurable and vary widely for mild, moderate, and severe psoriasis and possible adverse outcomes of methotrexate treatment. The process of elucidating individual patient utilities for various health outcomes can be used to incorporate patient preferences into the process of clinical decision making. Guidelines that are based solely on severity of symptoms, without input from patients on how they value such symptoms, must be questioned.
患者对健康结果的偏好可以通过称为效用的定量指标进行明确评估和表达。三种标准的效用评估方法已被用于量化患者的偏好，但这些方法此前尚未应用于皮肤病领域。使用基于计算机的交互式效用评估问卷U-Titer，对一家三级医疗中心的87名银屑病患者进行了访谈。通过垂直评分量表、时间权衡法和标准博弈法评估了三类银屑病严重程度以及甲氨蝶呤治疗潜在不良后果的效用。
患者为每种健康状态赋予了广泛的效用值。通过垂直评分量表获得的效用值与通过标准博弈法或时间权衡法获得的效用值相关性不佳。然而，通过标准博弈法和时间权衡法评估的效用值并无显著差异。年龄、性别和教育程度等患者特征与效用无关，也无法解释其中的差异。患者疾病严重程度的指标并不能预测所评估健康状态的效用。肝活检的效用相对较高，这表明患者对该检查的抵触情绪比预期要小。
效用，即患者对健康状态偏好的定量测量，对于轻度、中度和重度银屑病以及甲氨蝶呤治疗可能的不良后果是可测量的，且差异很大。阐明个体患者对各种健康结果的效用的过程可用于将患者偏好纳入临床决策过程。仅基于症状严重程度、而没有患者对这些症状重视程度的意见的指南，必须受到质疑。
