Institute of Social and Preventive Medicine (ISPM), University of Bern, Bern, Switzerland.
CTU Bern, University of Bern, Bern, Switzerland.
Trials. 2019 Jun 7;20(1):334. doi: 10.1186/s13063-019-3449-6.
'Conditional trial design' is a framework for efficiently planning new clinical trials based on a network of relevant existing trials. The framework considers whether new trials are required and how the existing evidence can be used to answer the research question and plan future research. The potential of this approach has not been fully realized.
We conducted an online survey among trial statisticians, methodologists, and users of evidence synthesis research using referral sampling to capture opinions about the conditional trial design framework and current practices among clinical researchers. The questions included in the survey were related to the decision of whether a meta-analysis answers the research question, the optimal way to synthesize available evidence, which relates to the acceptability of network meta-analysis, and the use of evidence synthesis in the planning of new studies.
In total, 76 researchers completed the survey. Two out of three survey participants (65%) were willing to possibly or definitely consider using evidence synthesis to design a future clinical trial and around half of the participants would give priority to such a trial design. The median rating of the frequency of using such a trial design was 0.41 on a scale from 0 (never) to 1 (always). Major barriers to adopting conditional trial design include the current regulatory paradigm and the policies of funding agencies and sponsors.
Participants reported moderate interest in using evidence synthesis methods in the design of future trials. They indicated that a major paradigm shift is required before the use of network meta-analysis is regularly employed in the design of trials.
“条件性试验设计”是一种基于相关现有试验网络高效规划新临床试验的框架。该框架考虑了是否需要新的试验，以及如何利用现有证据来回答研究问题和规划未来研究。该方法的潜力尚未得到充分实现。
我们采用 referral sampling 方法，对试验统计学家、方法学家和证据综合研究用户进行了在线调查，以了解他们对条件性试验设计框架的看法以及临床研究人员的当前实践情况。调查问卷中的问题涉及到是否需要进行 meta 分析来回答研究问题、如何优化合成现有证据（这与网络 meta 分析的可接受性有关）以及如何在新研究规划中使用证据综合等问题。
共有 76 名研究人员完成了调查。三分之二的调查参与者（65%）表示可能或肯定会考虑使用证据综合来设计未来的临床试验，大约一半的参与者会优先考虑这种试验设计。参与者对这种试验设计的使用频率的中位数评分为 0.41（范围从 0 到 1，其中 0 表示从不，1 表示总是）。采用条件性试验设计的主要障碍包括当前的监管范式以及资助机构和赞助商的政策。
参与者报告对使用证据综合方法设计未来试验的兴趣适中。他们表示，在网络 meta 分析在试验设计中得到广泛应用之前，需要进行重大的范式转变。
