Sutton Alexander J, Cooper Nicola J, Jones David R
Department of Health Sciences, University of Leicester, Leicester, UK.
BMC Med Res Methodol. 2009 Apr 30;9:29. doi: 10.1186/1471-2288-9-29.
Systematic review and meta-analysis currently underpin much of evidence-based medicine. Such methodologies bring order to previous research, but future research planning remains relatively incoherent and inefficient.
To outline a framework for evaluation of health interventions, aimed at increasing coherence and efficiency through i) making better use of information contained within the existing evidence-base when designing future studies; and ii) maximising the information available and thus potentially reducing the need for future studies.
The framework presented insists that an up-to-date meta-analysis of existing randomised controlled trials (RCTs) should always be considered before future trials are conducted. Such a meta-analysis should inform critical design issues such as sample size determination. The contexts in which the use of individual patient data meta-analysis and mixed treatment comparisons modelling may be beneficial before further RCTs are conducted are considered. Consideration should also be given to how any newly planned RCTs would contribute to the totality of evidence through its incorporation into an updated meta-analysis. We illustrate how new RCTs can have very low power to change inferences of an existing meta-analysis, particularly when between study heterogeneity is taken into consideration.
While the collation of existing evidence as the basis for clinical practice is now routine, a more coherent and efficient approach to planning future RCTs to strengthen the evidence base needs to be developed. The framework presented is a proposal for how this situation can be improved.
系统评价和荟萃分析目前是循证医学的重要基础。这些方法为以往的研究带来了秩序，但未来的研究规划仍相对缺乏连贯性且效率低下。
概述一个健康干预评估框架，旨在通过以下方式提高连贯性和效率：i）在设计未来研究时更好地利用现有证据库中包含的信息；ii）最大化可用信息，从而潜在地减少对未来研究的需求。
所提出的框架坚持认为，在进行未来试验之前，应始终考虑对现有随机对照试验（RCT）进行最新的荟萃分析。这样的荟萃分析应为关键设计问题提供信息，如样本量的确定。还考虑了在进行进一步的随机对照试验之前，使用个体患者数据荟萃分析和混合治疗比较模型可能有益的情况。还应考虑任何新计划的随机对照试验如何通过纳入更新的荟萃分析为整体证据做出贡献。我们说明了新的随机对照试验如何可能具有非常低的改变现有荟萃分析推断的能力，特别是在考虑研究间异质性时。
虽然将现有证据整理作为临床实践的基础现在已成为常规，但需要开发一种更连贯、更有效的方法来规划未来的随机对照试验，以加强证据基础。所提出的框架是关于如何改善这种情况的一项提议。
