Copay Anne G, Chung Andrew S, Eyberg Blake, Olmscheid Neil, Chutkan Norman, Spangehl Mark J
SPIRITT Research, St. Louis, Missouri.
Department of Orthopaedics, Mayo Clinic-Arizona, Phoenix, Arizona.
JBJS Rev. 2018 Sep;6(9):e1. doi: 10.2106/JBJS.RVW.17.00159.
The minimum clinically important difference (MCID) attempts to define the patient's experience of treatment outcomes. Efforts at calculating the MCID have yielded multiple and inconsistent MCID values. The purposes of this review were to describe the usage of the MCID in the most recent orthopaedic literature, to explain the limitations of its current uses, and to clarify the underpinnings of MCID calculation. Subsequently, we hope that the information presented here will help practitioners to better understand the MCID and to serve as a guide for future efforts to calculate the MCID. The first part of this review focuses on the upper-extremity orthopaedic literature. Part II will focus on the lower-extremity orthopaedic literature.
A review was conducted of the 2014 to 2016 publications in The Journal of Arthroplasty, The Journal of Bone & Joint Surgery, The American Journal of Sports Medicine, Foot & Ankle International, Journal of Orthopaedic Trauma, Journal of Pediatric Orthopaedics, and Journal of Shoulder and Elbow Surgery. Only clinical science articles utilizing patient-reported outcome measure (PROM) scores were included in the analysis. A keyword search was then performed to identify articles that calculated or referenced the MCID. Articles were then further categorized into upper-extremity and lower-extremity publications. MCID utilization in the selected articles was subsequently characterized and recorded.
The MCID was referenced in 129 (7.5%) of 1,709 clinical science articles that utilized PROMs: 52 (40.3%) of 129 were related to the upper extremity, 5 (9.6%) of 52 independently calculated MCID values, and 47 (90.4%) of 52 used previously published MCID values as a gauge of their own results. MCID values were considered or calculated for 16 PROMs; 12 of these were specific to the upper extremity. Six different methods were used to calculate the MCID. Calculated MCIDs had a wide range of values for the same PROM (e.g., 8 to 36 points for Constant-Murley scores and 6.4 to 17 points for American Shoulder and Elbow Surgeons [ASES] scores).
Determining useful MCID values remains elusive and is compounded by the proliferation of PROMs in the field of orthopaedics. The fundamentals of MCID calculation methods should be critically evaluated. If necessary, these methods should be corrected or abandoned. Furthermore, the type of change intended to be measured should be clarified: beneficial, detrimental, or small or large changes. There should also be assurance that the calculation method actually measures the intended change. Finally, the measurement error should consistently be reported.
The MCID is increasingly used as a measure of patients' improvement. However, the MCID does not yet adequately capture the clinical importance of patients' improvement.
最小临床重要差异（MCID）旨在界定患者对治疗结果的体验。计算MCID的努力产生了多个且不一致的MCID值。本综述的目的是描述MCID在最新骨科文献中的使用情况，解释其当前使用的局限性，并阐明MCID计算的基础。随后，我们希望这里呈现的信息将有助于从业者更好地理解MCID，并为未来计算MCID的努力提供指导。本综述的第一部分聚焦于上肢骨科文献。第二部分将聚焦于下肢骨科文献。
对《关节置换杂志》《骨与关节外科杂志》《美国运动医学杂志》《足与踝关节国际杂志》《骨科创伤杂志》《小儿骨科杂志》以及《肩肘外科杂志》2014年至2016年发表的文章进行综述。分析仅纳入使用患者报告结局测量（PROM）分数的临床科学文章。然后进行关键词搜索，以识别计算或引用了MCID的文章。文章随后进一步分为上肢和下肢出版物。随后对所选文章中MCID的使用情况进行特征描述和记录。
在1709篇使用PROMs的临床科学文章中，有129篇（7.5%）引用了MCID：129篇中的52篇（40.3%）与上肢相关，52篇中的5篇（9.6%）独立计算了MCID值，52篇中的47篇（90.4%）使用先前发表的MCID值作为其自身结果的衡量标准。针对16种PROM考虑或计算了MCID值；其中12种特定于上肢。使用了六种不同的方法来计算MCID。对于相同的PROM，计算出的MCID值范围很广（例如，Constant-Murley评分的MCID值为8至36分，美国肩肘外科医师学会[ASES]评分的MCID值为6.4至17分））。
确定有用的MCID值仍然难以捉摸，并且由于骨科领域中PROM的激增而变得更加复杂。MCID计算方法的基本原理应受到严格评估。如有必要，应纠正或摒弃这些方法。此外，应明确打算测量的变化类型：有益的、有害的或小的或大的变化。还应确保计算方法实际测量的是预期的变化。最后，应始终报告测量误差。
MCID越来越多地被用作衡量患者改善情况的指标。然而，MCID尚未充分体现患者改善情况的临床重要性。
