Transfer to the Local Stroke Center versus Direct Transfer to Endovascular Center of Acute Stroke Patients with Suspected Large Vessel Occlusion in the Catalan Territory (RACECAT): Study protocol of a cluster randomized within a cohort trial.

The primary endpoint based on the modified intention-to-treat population is the distribution of modified Rankin Scale scores at 90 days analyzed under a sequential triangular design. The maximum sample size is 1754 patients, with two planned interim analyses when 701 (40%) and 1227 patients have completed follow-up. Hypothesized common odds ratio is 1.35.