Washington University School of Medicine, Saint Louis, MO, USA.
The Spine Hospital, Columbia College of Physicians and Surgeons, 5141 Broadway, New York, NY 10034, USA.
Spine J. 2019 Aug;19(8):1319-1323. doi: 10.1016/j.spinee.2019.04.008. Epub 2019 Apr 12.
The minimal clinically important difference (MCID) is the smallest change in an outcomes instrument deemed relevant to a patient. MCID values proposed in spine research are limited by poor discriminative abilities to accurately classify patients as "improved" or "not improved." Furthermore, the MCID should not compare relative effectiveness between two groups of patients, though it is frequently used for this. The minimum detectable measurement difference (MDMD) is an alternative to the MCID in outcomes research. The MDMD must be greater than the MCID for the latter to be of value and the MDMD can compare change between groups.
The purpose of this study was to determine the MDMD for the Scoliosis Research Society-22r (SRS-22r) in adolescent idiopathic scoliosis (AIS) patients treated with surgery.
Retrospective cohort study from multi-center registry.
Patients treated surgically for AIS.
Self-reported SRS-22r.
An observational cohort of surgically treated AIS patients was queried for patients with complete baseline, 1-year, and 2-year SRS-22r data. The MDMD was calculated for SRS-22r domain and subscores. Effect size (ES) and standardized response mean were calculated to measure responsiveness of the SRS-22r to change. MDMD values were compared with MCID values. Research grants were received from DePuy Synthes Spine, EOS imaging, K2M, Medtronic, NuVasive, and Zimmer Biomet to Setting Scoliosis Straight Foundation.
One thousand two hundred and eighty-one AIS patients (1,034 female, 247 male, mean age 14.6 years) were analyzed. MDMD values were between 0.23 and 0.31. SRS-Pain MDMD was 0.3, greater than the MCID of 0.2. SRS-Activity MDMD was 0.24, greater than the MCID of 0.08. SRS-self-image MDMD was 0.3, less than the MCID of 0.98. Sixty-four percent of those with baseline SRS-self-image>4.0 improved MDMD or more, whereas only 14% improved beyond the MCID. ES and standardized response mean were highest for subscore and self-image.
The MDMD can compare the relevance of change in SRS-22r scores between groups of AIS patients. SRS-pain and SRS-activity MDMD values are greater than the MCID and should serve as the threshold for clinically relevant improvement. MDMD may help evaluate change in patients with baseline self-image>4.0.
最小临床重要差异（MCID）是被认为与患者相关的结果工具中最小的变化。脊柱研究中提出的 MCID 值受到较差的鉴别能力的限制，无法准确地将患者分类为“改善”或“未改善”。此外，MCID 不应该用于比较两组患者的相对疗效，尽管它经常被用于此目的。最小可检测测量差值（MDMD）是结果研究中 MCID 的替代方法。MCID 才有价值，MDMD 可以比较组间的变化。
本研究旨在确定接受手术治疗的青少年特发性脊柱侧凸（AIS）患者的 Scoliosis Research Society-22r（SRS-22r）的 MDMD。
多中心登记处的回顾性队列研究。
接受 AIS 手术治疗的患者。
自我报告的 SRS-22r。
对接受手术治疗的 AIS 患者进行了一项观察性队列研究，以查询具有完整基线、1 年和 2 年 SRS-22r 数据的患者。为 SRS-22r 域和子评分计算了 MDMD。效应量（ES）和标准化反应均值用于衡量 SRS-22r 对变化的反应能力。将 MDMD 值与 MCID 值进行比较。德普伊辛塔斯脊柱、EOS 成像、K2M、美敦力、纽瓦西夫和 Zimmer Biomet 向设定脊柱直基金会提供研究资助。
分析了 1281 名 AIS 患者（1034 名女性，247 名男性，平均年龄 14.6 岁）。MDMD 值在 0.23 到 0.31 之间。SRS-疼痛 MDMD 为 0.3，大于 0.2 的 MCID。SRS-活动 MDMD 为 0.24，大于 0.08 的 MCID。SRS-自我形象 MDMD 为 0.3，小于 0.98 的 MCID。基线 SRS-自我形象>4.0 的患者中有 64%改善 MDMD 或更多，而仅有 14%改善超过 MCID。亚评分和自我形象的 ES 和标准化反应均值最高。
MDMD 可比较 AIS 患者组之间 SRS-22r 评分变化的相关性。SRS-疼痛和 SRS-活动 MDMD 值大于 MCID，应作为临床相关改善的阈值。MDMD 可能有助于评估基线自我形象>4.0 的患者的变化。
