<International Circulation>: The advantage of this evidence-based approach is because it becomes more objective and more transparent.  So you think it leads to better， real usable results and guidelines about what really works?

　　《国际循环》：循证医学研究的优点是更客观更透明。那是否您认为它可以达到更好的疗效，它就真的会达到合理的效果，而且相关的指导原则真正起作用呢？
　　Prof. Oparil: Yes it does.  It eliminates a lot of the noise and gets at real true information.  What it does not do is have an answer for every little question.  Like people with one blue eye and one brown eye， we just haven’t looked into that subgroup.  Everyone wants those answers and there is always going to be some expert or personal opinion used in the practice of medicine.  If a person is sitting there and has a set of circumstances or set of problems， the physician has to do something.  You can’t just say that you ‘don’t really have any idea what is wrong with you and have no idea what to do with you.  See you later. Please leave the co-pay with the secretary.’  Sometimes you have to do things with some lack of evidence but we want to try to minimize that.  There is a tendency to be very zealous about， for example， getting the blood pressure as low as you can go.  Our guidelines for cardiovascular prevention， the official guidelines for lipids and blood pressure， and to a lesser extent obesity， there are many expert statements by the American College of Heart， the renal group， etc， that have things in them.  For example， the diabetes society might tell you you have to lower the blood pressure much lower in people with diabetes than in people without.  Other people who look at the evidence may not be so convinced and argue that diabetics are the same as other people.

　　Oparil教授： 是的。这种研究方法排除了很多干扰因素，并得到真实可靠的信息。它所不能解决的是，不能为每个小问题提供答案。就像人一只眼睛是蓝色另一只眼睛是棕色，我们只是没有考虑到这些亚组。每个人都希望获得这些问题的答案，这样总会出现一些运用于医学实践的专业知识或个人意见。如果一个人可以坐在那儿不动，设置一些事情或问题让医生去做。你不能只是说：“你真的没有任何想法？你是哪儿出问题了？不知道你自己要怎么做。那就请回见，请把预付款交给秘书”。有时候，在证据不充分的情况下都得要行动，但我们期望能尽量避免这种情况发生。有时候你会很热心地倾向于，比如，将血压降到你可以降到的水平。在我们的预防心血管疾病的指导原则，血脂和血压的官方指导原则，及轻度肥胖的指导原则中，都有许多来自美国心脏、肾脏等协会的专家声明。比如，糖尿病协会可能会告诉你，你必须将血压和血糖水平降到远低于非糖尿病患者的水平。其它调查这一证据的人可能不敢相信，他们认为糖尿病患者的血压和血糖控制应该与其他人一样。
　　<International Circulation>:But the lower blood pressure guideline for diabetics has been accepted around the world.

　　《国际循环》：但是目前全世界都接受将糖尿病患者血压降到更低水平这一指导原则。

　　Prof. Oparil:  It has become the trend.  Our task is to look at the real evidence that shows that.

　　Oparil教授：这已经成为一种趋势，我们的任务就是调查这些文献依据是否如实表述。

　　<International Circulation>: There are going to be areas where you don’t know what to say.  How much would you say in an area that there isn’t much evidence?  Would it be that you experts say something to fill the gaps?

　　《国际循环》：有些原则的内容可能是你不想谈论的。如果某些原则并无大量文献依据支持，就此您会说些什么？作为专家，您是否会为弥补这些不足而说些什么？
　　Prof. Oparil: Sid Smith showed the different levels of evidence.  The lowest is personal opinion， which actually isn’t evidence at all.  The procedure when we cannot decide or disagree is to consider alternatives and then vote on them.  We agree on most things and also cannot be inconclusive on important things.  For a few things we have yet to agree and I’m not sure how we are going to settle some of them.  It is sometimes really difficult because we look at many papers， many that get reviewed， and the methodologists decide whether it is a good paper or not.  We don’t decide.  The methodologists read literally what is published， not what someone thinks the investigators meant or what they think they did.  Generally there is much less information in these papers than you would think there is.  We reframe the question that the study said to be designed to achieve a certain threshold or go to a certain goal， and we find that there may have gone to a different goal.  This process eliminates a lot of published papers.

　　Oparil教授：Sid Smith曾列举过不同层次的文献依据。最低层次的是个人观点，其实这根本就算不上是依据。当我们不能决定或同意某项原则时，就必须考虑替代方案，并进行投票决定是否采用。我们对大多数原则是一致同意，但也可能对一些重要原则没有定论。有些原则我们暂未同意，我也不知道将如何解决。有时这项工作真的很难，因为我们查阅许多文献，然后由方法学家决定该文献是否合理，而我们不能做决定。方法学家查阅已发表的研究文献，而不是有的人所认为的研究者打算进行或已经完成的研究。通常，这些文献中的信息比你想像的要少很多。我们对这个问题重新定位，即通过研究来设定一个阈值或某个确定的目标，却发现这样做会导致另一个目标终点。在这个过程中，许多发表的文献就给淘汰了。