To the Editor We have some concerns about the recent CHOICE study1 that compared intra-arterial alteplase with placebo among patients with large vessel occlusion acute ischemic stroke after successful thrombectomy.
First, the primary study outcome was initially defined as the proportion of patients with an improved modified Treatment in Cerebral Ischemia score 10 minutes after the end of the experimental study treatment. However, this outcome was changed during the study to the currently reported primary outcome (ie, the proportion of patients with a modified Rankin Scale score of 0 to 1 at 90 days), which was previously a secondary outcome in both the registered () and published2 protocols. This modification was not clearly stated in the study1 and did not follow the CONSORT 2010 statement guidelines.3 Additional data on the original primary outcome would be helpful to interpret this trial, particularly because primary outcome switching may result in overestimation of treatment effect.4