I think part of it, though, comes back to the level of uncertainty. The more uncertain the data, the more innovative the product, the more you have to put in a robust surveillance system. In some cases, as a condition to having that drug approved, you have to set up a very robust surveillance system. The only way the clinicians are actually going to be able to prescribe that medication is in fact if they agree to do the monitoring and the surveillance. On the other hand, if you have something that has in fact been around for a long time, I think that requires a lesser level of surveillance.
So it really depends, I think, on the product we're talking about. As we've said before, when you're talking about very specific patient populations, in many cases you want to put in a very rigorous ongoing monitoring system in order to make sure you have a product that works and is also safe.