There is no curve. For the scaled score, a 70 on an easy exam should equal a 70 on a hard exam. They adjust the scaled score based on difficulty level. – Students taking exams at different times of year have advantages as they have covered more ground.Click to see full answer. Keeping this in view, are shelf exams pass fail?The standard passing score for the shelf examination has been set for all clerkships at the 6th percentile. A score in the 5ththpercentile or below is a fail. All students are required to take the shelf examination on the scheduled date.Subsequently, question is, how long is a shelf exam? The exam is a web-based test consisting of 110 questions, the majority of which are single-best answer multiple choice questions, administered over 2 hours and 45 minutes. Keeping this in consideration, how long does it take to get shelf exam scores back? 2-7 days How are Nbme shelf exams graded?The NBME shelf exams were originally scaled to a mean of 70 and a standard deviation of 8. Keep in mind, this is not recalculated every year. The actual average in a given year has tended to creep up and is usually somewhere in the low-to-mid 70s.