Conclusion: The results suggest that NAb testing reduces relapses and associated costs.
So this study looks at whether you should be testing for neutralising antibodies against beta interferons or not do anything. If you have neutralising antibodies then beta interferons stop working and relapses start to occur. This study shows that it is better to test as it saves money and will stop people relapsing unnecessarily. It seems obvious to do this as there are treatments that can work when beta interferon no longer does.
Shame the interferon companies did not develop a test to see who will responds to interferon treatment and how will not. Now that would be add to the cost-effectiveness.