The websites are different, the application process is different, the timing is different. Using the NBME application website for US grads only tells you IF your test has been graded. Even after my dean got my score, I could still register for Step 1. When you try and register for Step 1 it says 'try again' until your exam has been graded. The day your exam gets graded you can register for Step 1 (pretty scary but means nothing- everyone I know who could register for step 1 after their test had been graded passed). So the only thing you will know is which Wednesday your dean gets your score.