Dixon D O, Lagakos S W
Biostatistics Research Branch, Division of AIDS, National Institute of Allergy and Infectious Diseases, Bethesda, Maryland 20892-7620, USA.
Control Clin Trials. 2000 Feb;21(1):1-6; discussion 54-5. doi: 10.1016/s0197-2456(99)00042-2.
Consider the following situation: Two clinical trials are underway, closely related in terms of the interventions being compared and the target populations. In preparing for a planned interim analysis, the statistician for trial 1 finds that the results support a recommendation to stop the trial early. Should the statistician ask the investigators for trial 2 to make interim results of their trial available to the data and safety monitoring board (DSMB) for trial 1? If so, in what form? Would the answers change if the trial 1 results showed a strong but not convincing trend? What is the obligation of the trial 2 investigators to respond to such a request? What role do the two DSMBs have, either in initiating a request or in agreeing to respond to it? In this article, we examine this situation in some detail, having faced it occasionally in our own experience with clinical trials and DSMBs. The chief argument in favor of sharing data is that data from trial 2 are obviously relevant to the question being addressed by trial 1 and therefore ought to be available to those who must interpret the results from that trial. On the other hand, there are several reasons for not sharing interim data. For example, sharing is incompatible with the independence of the trials; the time for synthesizing evidence from both trials is after the two teams of investigators have presented the full analysis and interpretation of their separate trials. For this and other conceptual and practical reasons we conclude that it is better, in most cases, for DSMBs to consider only information that has already been made public in some form.
两项临床试验正在进行，在比较的干预措施和目标人群方面密切相关。在为计划中的中期分析做准备时，试验1的统计学家发现结果支持提前终止试验的建议。该统计学家是否应要求试验2的研究者将其试验的中期结果提供给试验1的数据与安全监测委员会（DSMB）？如果是，应以何种形式提供？如果试验1的结果显示出强烈但不令人信服的趋势，答案会改变吗？试验2的研究者有何义务回应这样的请求？两个DSMB在发起请求或同意回应请求方面扮演什么角色？在本文中，鉴于我们自己在临床试验和DSMB方面的经历中偶尔遇到过这种情况，我们将对此情形进行详细探讨。支持共享数据的主要论点是，试验2的数据显然与试验1所解决的问题相关，因此应该提供给那些必须解读该试验结果的人。另一方面，不共享中期数据有几个原因。例如，共享与试验的独立性不相容；综合两项试验证据的时机是在两组研究者分别对各自的试验进行全面分析和解读之后。出于这个以及其他概念和实际原因，我们得出结论，在大多数情况下，DSMB最好只考虑已经以某种形式公开的信息。
