Bult J R, Hunink M G, Tsevat J, Weinstein M C
Monitor Company, Cambridge, MA, USA.
Med Care. 1998 Apr;36(4):523-32. doi: 10.1097/00005650-199804000-00008.
Evidence in the literature suggests that the overall correlation between descriptive and valuational measures of health are weak to moderate. In this study, the relationship between descriptive health status measures, obtained using the Short-Form 36, and health values, measured with the time tradeoff, was explored.
Two groups of patients matched for age and gender were interviewed. One group comprised 139 human immunodeficiency virus (HIV)-infected patients; the other group comprised 124 primary care patients. The relationship between the SF-36 and the time tradeoff was estimated, assuming homogeneity across patients, using multiple regression analysis. Subsequently, the relationship was examined assuming heterogeneity across patients and using the expectation maximization algorithm in a maximum likelihood context (latent class analysis).
Four classes, representing 47%, 13%, 8%, and 32% of the population, respectively, were found. The overall percentage of variation explained under the assumption of a homogeneous relationship was only 33% as compared with 85% when heterogeneity was accounted for. Only three characteristics (educational level, employment status, and the SF-36 social functioning score) sufficed to generate a nearly perfect classification of the patients.
Heterogeneity across subjects should be taken into account in describing the relationship between health values and health status dimensions.
文献中的证据表明，健康描述性指标与评估性指标之间的总体相关性较弱至中等。在本研究中，探讨了使用简短健康调查问卷36项版本（Short-Form 36）获得的健康描述性状态指标与采用时间权衡法测量的健康价值观之间的关系。
对两组年龄和性别匹配的患者进行访谈。一组包括139名感染人类免疫缺陷病毒（HIV）的患者；另一组包括124名初级保健患者。使用多元回归分析，在假设患者间具有同质性的情况下估计简短健康调查问卷36项版本与时间权衡法之间的关系。随后，在假设患者间具有异质性的情况下，使用期望最大化算法在最大似然框架下（潜在类别分析）检验这种关系。
发现了四个类别，分别占总体的47%、13%、8%和32%。在假设关系同质的情况下，解释的变异总体百分比仅为33%，而异质性被考虑时这一比例为85%。仅三个特征（教育水平、就业状况和简短健康调查问卷36项版本的社会功能得分）就足以对患者进行近乎完美的分类。
在描述健康价值观与健康状况维度之间的关系时，应考虑个体间的异质性。
