The French study compared all patients who took growth hormone to the general population. But the two groups are not at all comparable: kids who receive the drug are far from normal.
这个例子又把我们带回到了相关关系和因果关系的难题上。那个法国研究把所有服用了增高激素的病人与普通法国人进行对比。但实际上这两个人群根本不存在可比性：服用这种药物的孩子与普通人根本不同。