PRECIS-2：基于研究目标的试验设计

The PRECIS-2 tool： designing trials that are fit for purpose

采用随机对照试验（RCT）评价的干预措施效果，涉及理论疗效和实际的临床效果两方面。PRECIS（Pragmatic—Explanatory Continuum Indicator Summary）通过评价RCT设计的解释性和实用性两方面的程度，指导研究者如何实行干预和试验设计，使RCT在内部真实性和外部真实性之间达到一个平衡。在临床试验方案设计过程中，PRECIS的作用逐渐被研究者所认同。为了确保试验的设计与结果相关联，便于患者、临床医生和政策决策者应用，国际多团队专家对PRECIS进行了修正和升级，提出了新的PRECIS-2。PRECIS-2的9个维度都是为了帮助试验设计者思考研究设计的预期效果与试验结果的一致性和特定场景的适用性。本文旨在介绍PRECIS-2的研发、基本原理、特点及应用，以期为国内临床试验设计、决策提供帮助。

To evaluate the intervention effects of randomized controlled trials （RCT） involved in theoretical efficacy and actual clinical outcome （effectiveness）. Pragmatic-Explanatory Continuum Indicator Summary （PRECIS） is a tool to help researchers make decisions in study design which is consistent with the intended purpose of their trial which can be used in the design of RCT to balance the internal validity and external validity. The role of PRECIS has been gradually recognized in the practice of designing clinical trials. To ensure that the design choices are concordant with the intention and the facilitation of use set by patients, clinicians and policy makers, a new PRECIS-2 tool has been developed by mangy international team experts under modification and upgrading the existing PRECIS. The PRECIS-2 tool mainly focuses on trial design choices which determining the applicability of a trial. PRECIS-2 has nine domains, with each of them intends to help the researchers consider the consequences of that design decision in terms of the applicability of the results under particular setting. The purpose of this paper is to introduce the development, basic principle, characteristics and application of PRECIS-2 for the designers and decision makers when working on clinical trials.