The Utility of Domain-Specific End Points in Acute Stroke Trials

Domain-specific endpoints are assessments that correspond to the output of individual neural systems and are useful for capturing treatment effects on specific behaviors. By contrast, global endpoints combine several attributes into a single score and are useful for capturing broad treatment effects in a summary way. While global endpoints have become the de facto mechanism required to define benefit in stroke trials, they also have important limitations, some of which might be addressed by simultaneously measuring domain-specific endpoints. Substantial opportunity remains to identify quantifiable patient benefit that would otherwise not be captured by global endpoints. Potential advantages of incorporating domain-specific endpoints in acute stroke trials are discussed, such as increased granularity of measurement, improved understanding of how therapies affect the brain between acute treatment and day 90, and optimized therapeutic translation. Potential disadvantages are also considered, including time and cost of administering domain-specific endpoints, as well as statistical implications. Domain-specific endpoints and global endpoints are not mutually exclusive, and both capture clinical benefits to patients. Incorporating a broader set of outcome assessments in stroke trials, including both global and domain-specific endpoints, is warranted.