反复尝试。如何避免常见的已发表临床试验的局限性。
Trial and error. How to avoid commonly encountered limitations of published clinical trials.
机构信息
Division of Cardiology, Cedars-Sinai Medical Center, and the David Geffen School of Medicine, University of California, Los Angeles, California 90048-1804, USA.
出版信息
J Am Coll Cardiol. 2010 Feb 2;55(5):415-27. doi: 10.1016/j.jacc.2009.06.065.
The randomized controlled clinical trial is the gold standard scientific method for the evaluation of diagnostic and treatment interventions. Such trials are cited frequently as the authoritative foundation for evidence-based management policies. Nevertheless, they have a number of limitations that challenge the interpretation of the results. The strength of evidence is often judged by conventional tests that rely heavily on statistical significance. Less attention has been paid to the clinical significance or the practical importance of the treatment effects. One should be cautious that extremely large studies might be more likely to find a formally statistically significant difference for a trivial effect that is not really meaningfully different from the null. Trials often employ composite end points that, although they enable assessment of nonfatal events and improve trial efficiency and statistical precision, entail a number of shortcomings that can potentially undermine the scientific validity of the conclusions drawn from these trials. Finally, clinical trials often employ extensive subgroup analysis. However, lack of attention to proper methods can lead to chance findings that might misinform research and result in suboptimal practice. Accordingly, this review highlights these limitations using numerous examples of published clinical trials and describes ways to overcome these limitations, thereby improving the interpretability of research findings.
随机对照临床试验是评估诊断和治疗干预措施的黄金标准科学方法。此类试验经常被引用为循证管理政策的权威基础。然而,它们存在许多限制,这些限制对结果的解释提出了挑战。证据的强度通常通过传统的测试来判断,这些测试严重依赖于统计学意义。对于治疗效果的临床意义或实际重要性,关注较少。人们应该谨慎,因为非常大型的研究可能更容易发现一个形式上具有统计学意义的差异,而这种差异对于与零值没有真正显著差异的微小效果来说并没有真正有意义。试验通常采用复合终点,虽然它们能够评估非致死性事件,并提高试验效率和统计精度,但存在许多潜在的缺点,这些缺点可能会破坏从这些试验中得出的结论的科学有效性。最后,临床试验经常进行广泛的亚组分析。然而,如果不注意适当的方法,可能会导致偶然发现,这些发现可能会误导研究并导致实践效果不佳。因此,本综述使用大量已发表的临床试验实例来强调这些局限性,并描述克服这些局限性的方法,从而提高研究结果的可解释性。