Department of Orthopedic Surgery, Center for Musculoskeletal Research, Vanderbilt University Medical Center, 1215 21st Ave South, Medical Center East, South Tower, Suite 4200, Nashville, TN 37232, USA.
Department of Neurological Surgery, Vanderbilt University Medical Center, 1161 21st Ave South, T4224 Medical Center North, Nashville, TN 37232, USA.
Spine J. 2020 Jun;20(6):847-856. doi: 10.1016/j.spinee.2020.01.010. Epub 2020 Jan 28.
Minimum clinically important difference (MCID) for patient-reported outcome measures is commonly used to assess clinical improvement. However, recent literature suggests that an absolute point-change may not be an effective or reliable marker of response to treatment for patients with low or high baseline patient-reported outcome scores. The multitude of established MCIDs also makes it difficult to compare outcomes across studies and different spine surgery procedures.
To determine whether a 30% reduction from baseline in disability and pain is a valid method for determining clinical improvement after lumbar spine surgery.
Retrospective analysis of prospective data from a national spine registry, the Quality Outcomes Database.
There were 23,280 participants undergoing elective lumbar spine surgery for degenerative disease who completed a baseline and follow-up assessment at 12 months.
Patient-reported disability (Oswestry Disability Index [ODI]), back and leg pain (11-point Numeric Rating Scale [NRS]), and satisfaction (NASS scale).
Patients completed baseline and a 12-month postoperative assessment to evaluate the outcomes of disability, pain, and satisfaction. The change in ODI and NRS pain scores was categorized as met (≥30%) or not met (<30%) percent reduction MCID. The 30% reduction from baseline was compared with a wide range of well-established absolute point-change MCID values. The relationship between 30% reduction and absolute change values and satisfaction were primarily compared using receiver operating characteristic (ROC) curves, area under the curve (AUROC), and logistic regression analyses. Analyses were conducted for overall scores and for disability and pain severity categories and by surgical procedure.
Thirty percent reduction in ODI and back and leg pain predicted satisfaction with more accuracy than absolute point-change values for the total population and across all procedure categories (p<.001), except for when compared with the highest absolute point-change threshold for leg pain (3.5-point reduction). The largest AUROC differences, in favor of 30% reduction, were found for the lowest disability (ODI 0-20%: 21.8%) and bed-bound disability (ODI 81%-100%: 13.9%) categories. For pain, there was a 3.4%-12.4% and 1.3%-9.8% AUROC difference for no/mild back and leg pain (NRS 0-4), respectively, in favor of a 30% reduction threshold.
A 30% reduction MCID either outperformed or was similar to absolute point-change MCID values. Results indicate that a 30% reduction (baseline to 12 months after surgery) in disability and pain is a valid method for determining clinically relevant improvement in a broad spine surgery population. Furthermore, a 30% reduction was most accurate for patients in the lowest and highest disability and lowest pain severity categories. A 30% reduction MCID allows for a standard cut-off for disability and pain that can be used to compare outcomes across various spine surgery procedures.
最小临床重要差异（MCID）常用于评估患者报告的结局的临床改善情况。然而，最近的文献表明，对于基线患者报告的结局得分较低或较高的患者，绝对的点变化可能不是治疗反应的有效或可靠标志物。众多已确立的 MCID 也使得难以在不同的脊柱手术程序和研究之间比较结果。
确定腰椎手术后，残疾和疼痛从基线降低 30%是否是确定临床改善的有效方法。
对全国脊柱登记处——质量结果数据库中的前瞻性数据进行回顾性分析。
有 23280 名接受择期腰椎退行性疾病手术的患者完成了基线和 12 个月时的随访评估。
患者报告的残疾（Oswestry 残疾指数[ODI]）、腰背疼痛（11 点数字评定量表[NRS]）和满意度（NASS 量表）。
患者完成基线和 12 个月术后评估，以评估残疾、疼痛和满意度的结果。ODI 和 NRS 疼痛评分的变化分为达到（≥30%）或未达到（<30%）百分比 MCID 降低。将基线的 30%降低与广泛的既定绝对点变化 MCID 值进行比较。主要使用受试者工作特征（ROC）曲线、曲线下面积（AUROC）和逻辑回归分析来比较 30%降低与绝对变化值与满意度之间的关系。分析针对总体评分以及残疾和疼痛严重程度类别进行，并按手术程序进行。
ODI 和腰背疼痛的 30%降低比总人群和所有手术类别中的绝对点变化值更能准确预测满意度（p<.001），除了与腿部疼痛的最高绝对点变化阈值（3.5 点降低）相比。有利于 30%降低的最大 AUROC 差异在最低残疾（ODI 0-20%：21.8%）和卧床不起的残疾（ODI 81%-100%：13.9%）类别中发现。对于疼痛，无/轻度腰背疼痛（NRS 0-4）的 AUROC 差异分别为 3.4%-12.4%和 1.3%-9.8%，有利于 30%降低阈值。
30%的 MCID 降低要么优于要么与绝对点变化 MCID 值相当。结果表明，残疾和疼痛从基线降低 30%（术后 12 个月）是确定广泛脊柱手术人群中临床相关改善的有效方法。此外，30%的降低对最低和最高残疾和最低疼痛严重程度类别的患者最准确。30%的 MCID 降低允许为残疾和疼痛设定一个标准的截止值，可用于比较不同脊柱手术程序的结果。
