OK, that's a good source, we need to note this view in the article and attribute it to Ernst. We also need to note the views of other authors that there is no significant difference and discuss the research as a whole. Obviously we can not take any particular stance ourselves on if the two types of SM are comparable (that would indeed be OR), so our discussion of this point needs to summarise both the research that used all the available evidence on SM, and the smaller amount of research that focused specifically on CSM. Does that seem fair?