Methods:
Stroke
REGRESSION, STROKE
We used data of the Interventional Management of Stroke (IMS) III trial. The modified Rankin Scale (mRS) at 90 days was assessed by local assessors who were unaware of treatment allocation. To assess success of blinding, each assessor was asked to guess the patient’s treatment allocation. We assessed whether the percentage of correct guesses was higher than chance (i.e. 50%). The association between correctly guessed treatment allocation and the mRS at 90 days was analyzed with ordinal logistic regression stratified by treatment allocation. We tested for interaction of correctly versus incorrectly guessed treatment allocation with actual treatment allocation on the mRS. Patients with missing data on guessed treatment allocation and patients who died prior to 90-day assessment were excluded.