School of Medicine, Georgetown University, Washington, DC, USA.
Department of Orthopaedic Surgery, MedStar Georgetown University Hospital, Washington, DC, USA.
Am J Sports Med. 2021 Aug;49(10):2827-2833. doi: 10.1177/0363546520969973. Epub 2020 Nov 19.
Evidence-based medicine utilizes data to inform clinical decision making, despite the ability of a small number of outcome reversals to change statistical significance. values are common measurements of statistical significance that possess inherent flaws. The inclusion of the fragility index (FI) and fragility quotient (FQ) may provide a clearer conveyance of statistical strength.
PURPOSE/HYPOTHESIS: The purpose was to examine the statistical stability of studies comparing hamstring tendon and bone-patellar tendon-bone autografts in primary single-bundle anterior cruciate ligament reconstruction with independent tunnel drilling. We hypothesized that the findings of these studies are vulnerable to a small number of outcome event reversals, often fewer than the number of patients lost to follow-up.
Systematic review.
Comparative studies and randomized controlled trials (RCTs) published in 10 leading orthopaedic journals between 2000 and 2020 were analyzed. Statistical significance was defined as a value ≤.05. FI for each outcome was determined by the number of event reversals necessary to alter significance. FQ was calculated by dividing the FI by the respective sample size.
Of the 1803 studies screened, 643 met initial search criteria, with 18 comparative studies ultimately included for analysis, 8 of which were RCTs. A total of 114 outcomes were examined. Overall, the mean (interquartile range) FI and FQ were 3.77 (2-4) and 0.040 (0.016-0.055), respectively. The FI was less than the number of patients lost to follow-up for 76.3% of outcomes.
Studies examining graft choice for anterior cruciate ligament reconstruction may not be as statistically stable as previously thought. Comparative studies and RCTs are at substantial risk for statistical fragility, with few event reversals required to alter significance. The reversal of <4 outcome events in a treatment group can alter the statistical significance of a given result; this is commonly fewer than the number of patients lost to follow-up. Future comparative study analyses might consider including FI and FQ with values in their statistical analysis.
循证医学利用数据为临床决策提供信息，尽管少量结果逆转会改变统计显著性。 值是常见的统计显著性测量方法，具有内在的缺陷。纳入脆弱指数（FI）和脆弱性分数（FQ）可能更清楚地传达统计强度。
目的/假设：本研究旨在检查比较腘绳肌腱和骨-髌腱-骨自体移植物在独立隧道钻孔的原发性单束前交叉韧带重建中研究的统计稳定性。我们假设这些研究的发现容易受到少数结果事件逆转的影响，通常少于失访患者的数量。
系统评价。
分析了 2000 年至 2020 年 10 种主要骨科期刊发表的比较研究和随机对照试验（RCT）。统计显著性定义为 值≤.05。通过改变显著性所需的事件逆转数来确定每个结果的 FI。FQ 通过将 FI 除以各自的样本量来计算。
在筛选的 1803 项研究中，有 643 项符合初始搜索标准，最终有 18 项比较研究被纳入分析，其中 8 项为 RCT。共检查了 114 个结果。总体而言，平均（四分位距）FI 和 FQ 分别为 3.77（2-4）和 0.040（0.016-0.055）。76.3%的结果的 FI 小于失访患者的数量。
检查前交叉韧带重建中移植物选择的研究可能不如以前认为的那样具有统计学稳定性。比较研究和 RCT 存在很大的统计脆弱性风险，只需少数结果逆转即可改变显著性。在一个治疗组中，<4 个结果事件的逆转可以改变给定结果的统计显著性；这通常少于失访患者的数量。未来的比较研究分析可能需要在其统计分析中包含 FI 和 FQ 以及 值。
