A transition period is starting for USMLE Step 3 which will make modifications to the exam pattern and MCQs starting from February 11, 2013. The examinees will experience a minor decrease in the number of multiple-choice questions (MCQs) in current forms of the Step 3 examination.

Although the transition will occur quickly at many test centers, there may be some exam centers where the changes may take slightly longer. The transition period will likely take approximately 4 weeks.

The  length of the examination day will remain unchanged and the scores on new and old forms will be both be comparable to each other.

However, score reports for Step 3 examinations administered from the week of February 11, 2013 through early May 2013 will be on Wednesday, June 5, 2013.

Reference: http://www.usmle.org