Psycho-oncology Co-operative Research Group, School of Psychology, Brennan MacCallum Building (A18), University of Sydney, NSW 2006, Australia.
Expert Rev Pharmacoecon Outcomes Res. 2011 Apr;11(2):171-84. doi: 10.1586/erp.11.9.
The minimal important difference (MID) is a phrase with instant appeal in a field struggling to interpret health-related quality of life and other patient-reported outcomes. The terminology can be confusing, with several terms differing only slightly in definition (e.g., minimal clinically important difference, clinically important difference, minimally detectable difference, the subjectively significant difference), and others that seem similar despite having quite different meanings (minimally detectable difference versus minimum detectable change). Often, nuances of definition are of little consequence in the way that these quantities are estimated and used. Four methods are commonly employed to estimate MIDs: patient rating of change (global transition items); clinical anchors; standard error of measurement; and effect size. These are described and critiqued in this article. There is no universal MID, despite the appeal of the notion. Indeed, for a particular patient-reported outcome instrument or scale, the MID is not an immutable characteristic, but may vary by population and context. At both the group and individual level, the MID may depend on the clinical context and decision at hand, the baseline from which the patient starts, and whether they are improving or deteriorating. Specific estimates of MIDs should therefore not be overinterpreted. For a given health-related quality-of-life scale, all available MID estimates (and their confidence intervals) should be considered, amalgamated into general guidelines and applied judiciously to any particular clinical or research context.
最小有意义差异（MID）是一个在努力解释健康相关生活质量和其他患者报告结局的领域中具有即时吸引力的短语。该术语可能会引起混淆，因为有几个术语在定义上仅略有不同（例如，最小临床重要差异、临床重要差异、最小可检测差异、主观显著差异），而其他术语尽管含义不同，但看起来却相似（最小可检测差异与最小可检测变化）。通常，这些数量的估计和使用方式并不会对定义的细微差别产生太大影响。估计 MID 通常采用以下四种方法：患者对变化的评分（全局过渡项目）；临床锚定物；测量误差标准；和效应量。本文对这些方法进行了描述和评价。尽管这个概念很有吸引力，但实际上并不存在通用的 MID。实际上，对于特定的患者报告结局工具或量表，MID 并不是一个不变的特征，而是可能因人群和环境而异。在群体和个体水平上，MID 可能取决于手头的临床环境和决策、患者开始时的基线以及他们是在改善还是恶化。因此，不应过度解释特定的 MID 估计值。对于给定的健康相关生活质量量表，应考虑所有可用的 MID 估计值（及其置信区间），将其合并为一般指南，并明智地应用于任何特定的临床或研究环境。
