We don't have an equivalent tool for MS yet, How far behind do you think the MS field is and what would we need to do to close that gap?

I think we're really close and I think it's worth reflecting on why Parkinson's disease field is so much further ahead than MS.

Historically, multiple sclerosis wasn't thought to have a prodromal phase until relatively recently, which is a real shame because in Parkinson's disease, they were already talking about the concept of a prodromal phase back in the 80s.

And today it's well recognised that Parkinson's disease has a lengthy prodromal phase lasting 10 or more years.

And now that they have created and validated research criteria, to identify people in the prodromal phase of Parkinson's based on decades of knowledge that's been accrued.

So we've got a lot of catch up there here in MS.

So sort of echoing what you said, they're combining traditional risk markers.

So does that really improve our arguments towards screening? Or do you think it just reveals the complexity in this space? Helen, maybe you first.