Background:

Fragility analysis is increasingly utilized to evaluate the robustness of results within the orthopaedic literature and has frequently revealed instability of reported outcomes.

Purpose/Hypothesis:

The purpose of this investigation was to utilize a fragility analysis to evaluate the stability of reported results in the patellofemoral instability (PFI) literature. We hypothesized the demonstration of significant fragility in patellofemoral research to be similar to that identified throughout other areas of the orthopaedic literature.

Study Design:

Systematic review; Level of evidence, 4.

Methods:

The PubMed database was queried from January 1, 2000, to October 10, 2020 for comparative trials in 10 prominent orthopaedic journals that reported dichotomous outcomes related to the management of PFI. The fragility index (FI) and the fragility quotient (FQ) were calculated for each individual outcome event, and the overall FI and FQ were determined for all included studies.

Results:

A total of 22 comparative studies comprising 11 randomized controlled trials and 11 nonrandomized trials were included for the analysis. A total of 75 outcome events underwent a fragility analysis and revealed a median FI and FQ of 3 (interquartile range [IQR], 1-5) and 0.043 (IQR, 0.018-0.081), respectively. Also 27% of included studies reported loss to follow-up greater than the overall FI, therefore suggesting the maintenance of the follow-up may have resulted in the reversal of significance.

Conclusion:

The result of the comprehensive fragility analysis demonstrated a lack of robustness in PFI research with the alteration of only a few outcome events required to reverse statistical significance. We therefore recommend the triple reporting of the P value, the FI, and the FQ to aid in the interpretation of the statistical integrity of future comparative trials in the PFI literature.

中文翻译：

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髌股关节不稳定研究中统计意义的脆弱性：系统回顾

背景：

脆弱性分析越来越多地用于评估骨科文献中结果的稳健性，并且经常揭示报告结果的不稳定性。

目的/假设：

本研究的目的是利用脆性分析来评估髌股关节不稳 (PFI) 文献中报告结果的稳定性。我们假设髌股关节研究中显着脆弱性的证明与骨科文献中其他领域所发现的相似。

学习规划：

系统审查；证据等级，4。

方法：

从 2000 年 1 月 1 日到 2020 年 10 月 10 日查询了 PubMed 数据库，以在 10 种著名的骨科期刊中进行比较试验，这些期刊报告了与 PFI 管理相关的二分类结果。计算每个单独结果事件的脆弱性指数 (FI) 和脆弱性商数 (FQ)，并确定所有纳入研究的总体 FI 和 FQ。

结果：

共有 22 项比较研究包括 11 项随机对照试验和 11 项非随机试验被纳入分析。共有 75 个结果事件进行了脆弱性分析，显示 FI 和 FQ 中位数分别为 3（四分位距 [IQR]，1-5）和 0.043（IQR，0.018-0.081）。此外，27% 的纳入研究报告失访率高于总体 FI，因此表明维持随访可能导致显着性逆转。

结论：

综合脆弱性分析的结果表明 PFI 研究缺乏稳健性，只需改变少数结果事件即可扭转统计显着性。因此，我们建议对P值、FI 和 FQ 进行三重报告，以帮助解释 PFI 文献中未来比较试验的统计完整性。