My short notice to this hot thema :
Problem with HD results from different countries is basicaly in not comparable valuation. Most countries have only 5 grades
A, B, C, D, E) and short descriptions (normal, borderline, mild, moderate, severe). Internationally is no described, whats means the descriptions. When is it e.g. "mild" and " when already "moderate" ? And is not only this problem. Some countries have totally different system and grades. So that is practically not possible to compare the results from different countries. More about it on
http://www.grsk.org (in german language only).