Kashir Imad, Olaonipekun Emmanuel, Rajagopalan Jananey, Khan Moin, Adili Anthony, Mbuagbaw Lawrence, Madden Kim
Research Institute of St. Joseph's Healthcare Hamilton, Canada.
Royal College of Surgeons in Ireland, Department of Medicine, Ireland.
J Orthop. 2025 Jun 4;69:216-221. doi: 10.1016/j.jor.2025.05.065. eCollection 2025 Nov.
Randomized controlled trials (RCTs) are considered the gold standard in evidence-based medicine, providing high-quality evidence for the effectiveness of interventions in healthcare. However, the quality of RCTs can vary substantially. One aspect of methodological quality that has recently garnered interest is the fragility index (FI) which is a metric indicating how many event changes would lead to a change the significance of a study's results. Surgical RCTs, especially in orthopedic fields like hip and knee arthroplasty, have been shown to have high fragility, raising concerns about their reliability. This methodological study aims to describe the statistical fragility of RCTs in hip and knee arthroplasty over the past decade, with a secondary objective of determining the study characteristics associated with fragility.
We conducted a systematic search of Medline and Embase databases for RCTs published between 2012 and 2022, focusing on hip and knee arthroplasty. Trials were included if they had a 1:1 parallel design and reported at least one statistically significant outcome. FI were calculated for both dichotomous and continuous outcomes using established methods. We extracted data such as sample size, study characteristics, and statistical measures. Multivariable regression was used to explore relationships between FI and study characteristics such as sample size, intervention type, and region.
From 16,214 records, 140 studies met the inclusion criteria. The median FI for dichotomous outcomes was 2, interquartile range (IQR) = 4, while the median continuous FI (CFI) was 8.85 (IQR 14.4), indicating higher robustness for continuous outcomes. No significant associations were found between FI and variables like region, year of publication, or sample size.
Hip and knee arthroplasty trials often exhibit statistical fragility, particularly those reporting dichotomous outcomes. These fragile findings suggest the need for more robust RCT designs in orthopedic research. Incorporating FI into sample size calculations could improve trial stability and ensure more reliable outcomes that better inform clinical guidelines and patient care.
随机对照试验（RCT）被认为是循证医学的金标准，为医疗保健干预措施的有效性提供高质量证据。然而，RCT的质量可能有很大差异。方法学质量的一个最近引起关注的方面是脆弱性指数（FI），它是一个指标，表明多少事件变化会导致研究结果的显著性发生变化。手术RCT，特别是在髋关节和膝关节置换等骨科领域的RCT，已被证明具有较高的脆弱性，这引发了对其可靠性的担忧。这项方法学研究旨在描述过去十年中髋关节和膝关节置换RCT的统计脆弱性，次要目标是确定与脆弱性相关的研究特征。
我们对Medline和Embase数据库进行了系统检索，以查找2012年至2022年发表的关于髋关节和膝关节置换的RCT。如果试验采用1:1平行设计并报告了至少一项具有统计学显著性的结果，则纳入试验。使用既定方法计算二分法和连续型结果的FI。我们提取了样本量、研究特征和统计量等数据。使用多变量回归来探讨FI与样本量、干预类型和地区等研究特征之间的关系。
从16214条记录中，140项研究符合纳入标准。二分法结果的FI中位数为2，四分位间距（IQR）=4，而连续型FI（CFI）中位数为8.85（IQR 14.4），表明连续型结果具有更高的稳健性。未发现FI与地区、发表年份或样本量等变量之间存在显著关联。
髋关节和膝关节置换试验通常表现出统计脆弱性，特别是那些报告二分法结果的试验。这些脆弱的结果表明，骨科研究需要更稳健的RCT设计。将FI纳入样本量计算可以提高试验稳定性，并确保获得更可靠的结果，从而更好地为临床指南和患者护理提供信息。
