<International Circulation>: Since 1993 TOAST classification system has been the most widely used classification system in the recent literature;  what are the strengths and weaknesses of this system?

  《国际循环》：自1993年以来，TOAST分型标准在文献报道中得到广泛应用，这一分型体系有何优缺点？
    Prof Pierre Amarenco: TOAST was a very useful method used to analyse a clinical trial using a heparinoid versus placebo. The purpose of the trial was to see whether this particular heparinoid was effective in increasing the likelihood of favourable outcomes after ischemic stroke. Finally the trial was negative but it turned out this classification was used for other purposes such as looking for new genetic markers and risk factors. Almost 20 years later it was no longer possible to accept such a system which was so biased because TOAST only classified patients with atherothrombotic disease only if they had a tight stenosis forgetting all the patients who have some form of atherosclerotic disease. With the new ASCO classification patients who have atherosclerotic disease will be classified in A whatever the cause it is.  If it is an atherosclerotic disease related to the stroke then it is classified in A1， possibly related to the stroke in A2 and unlikely related to the stroke as A3.  This is the main concept of the ASCO classification. In addition TOAST only classified a few patients with small vessel disease group forgetting all the others with small vessel disease which are classified in the artherothrombotic， cardio thrombotic or other cause group. All these patients are not taken into account in the TOAST classification but in the ASCO classification all patients with some form of small vessel disease have an S; S1 if it is most likely related to the stroke， S2 if it possibly related to the stroke and S3 if there is some form of small vessel disease unrelated to the stroke. So when you analyse genetic polymorphism or a new risk factor you will take all your S cohorts but in TOAST you will only take a small proportion classified with small vessel disease. These are very different classifications and I think we need to take into account all patients who have the same disease whether it is a weak form of the disease or a strong form. 

    皮埃尔教授：TOAST是分析一项类肝素与安慰剂对比临床试验的一种非常有价值的方法。该试验旨在研究类肝素药物是否能够  改善缺血性卒中患者的预后。虽然试验结果呈阴性，但TOAST分型被用于寻找新的遗传及危险因素等其他方面。但由于TOAST只能用于存在严重狭窄的动脉硬化血栓形成患者的分型，而不适用于具有某些动脉粥样硬化（AS）病变的所有患者，因此近20年后的今天，我们不可能再接受一个像TOAST一样如此片面的标准。而新的ASCO分型中，所有AS患者均归为A型，无论病因如何；与卒中相关的AS病变分为A1，可能相关者为A2，无关的AS病变则为A3，这是ASCO分型的主要概念。此外，TOAST仅对少数小血管病变患者进行了分型，而无法对动脉粥样血栓形成、心源性栓子和其他病因的小动脉病变进行分型。在TOAST分型中未被考虑到的这部分小血管病变在ASCO分型中均归入S型：极有可能与卒中相关者为S1，可能相关的病变为S2，与卒中无关则为S3。当对基因多态性或一个新的危险因素进行分析时，采用ASCO分型可包括S型所有患者，而采用TOAST分型只能纳入一小部分小血管病变uanzh。这是两种非常不同的分型方法，无论疾病的表现是轻是重，我们应将患有同类疾病的所有患者全部考虑进去。