Calculation of Course/Clerkship Raw Score, TScore, TScore Average, and Ranking Statistics
Course/clerkship raw score
A raw score is a numerical grade awarded in a preclinical course or a clerkship. Raw scores are not awarded for junior selectives, Special Topics, coenrolled electives, Scholarly Activity, senior courses, and Medical Scientist Training Program courses. Raw scores are on a scale of 0100 with 70=passing. The method for calculating a raw score is determined by the course/clerkship director, with the following restrictions:

 Raw scores are reported as integers. Scores less than 70 are truncated (e.g., 69.889=69), and scores 70 or higher are rounded up for decimal values of .5 or greater (e.g., 70.513=71, 71.488=71).
 If a student fails a preclinical course and is allowed to take a makeup test in order to pass, the raw score reported is the original (failing) score.
 If a clerkship student has to repeat the NBME Subject Exam, the score from the first attempt is used in calculating the clerkship raw score. If the student passes the second attempt, the calculated raw score based on the first NBME score is reported, even if it is below 70. If the student fails the second attempt, he/she fails the clerkship, and the clerkship raw score must be less than 70. Thus, if the student fails the second attempt and the computed clerkship raw score is still 70 or greater, the reported raw score is set to 69.
Course/clerkship Tscore
Course and clerkship raw scores are converted to Tscores to maintain comparability of scores across courses, years and curriculum changes. A Tscore is a commonly used standard score that indicates the position of a raw score relative to the mean of a group, expressed in standard deviation (SD) units. A Tscore of 50 corresponds to the group mean; a Tscore of 60 is one SD above the group mean; a Tscore of 40 is one SD below the mean, and so on. A Tscore distribution always has a mean of 50 and a SD of 10, regardless of the underlying mean and SD for raw scores, so each preclinical course and clerkship has a mean Tscore of 50 and an SD of 10. The formula for calculating a Tscore is:
Tscore = 50 + [10 x ((raw score – mean)/SD)]
The mean and SD for a preclinical course are based on students taking the course during the same offering (time period). For clerkships, the mean and SD are based on active students applying for residency in the same year.
Tscore Average (TSA)
A TSA is a weighted average of course/clerkship Tscores for a student during a given training phase. Separate TSA’s are calculated for preclinical courses, clerkships, and overall. The overall TSA is used for AOA nominations, honors, and for class rank reported in a student’s residency application. If a student repeats a course or clerkship, both Tscores are included in the TSA. Course/clerkship weights are determined by the Medical Education Committee.
The following example illustrates the calculations:
Training Phase 
Course or Clerkship 
Tscore 
Weight 
Weight x Tscore 
TSA 
Preclinical 
Course 1 
50 
8 
400 

Course 2 
65 
4 
260 

Preclinical Sum = 
12 
660 
55.0 

Clerkship 
Clerkship 1 
50 
4 
200 

Clerkship 2 
60 
8 
480 

Clerkship Sum = 
12 
680 
56.7 

Overall Sum = 
24 
1340 
55.8 
The formula for TSA is [Sum of (Weight x Tscore)] divided by [Sum of Weights]. Thus, Preclinical TSA = 660 / 12 = 55.0, Clerkship TSA = 680 / 12 = 56.7, and Overall TSA = 1340 / 24 = 55.8. TSA’s are rounded to one decimal place.
Ranking statistics (percentiles and quartiles)
A percentile rank is calculated for Tscores in preclinical courses and clerkships and for each type of TSA. For preclinical course Tscores, the “ranking population” consists of students taking the course during the same offering (time period). For clerkship Tscores and for all TSA’s, the ranking population consists of active students applying for residency in the same year.
Percentile rank can be interpreted as the percent of students in the ranking population falling below a given Tscore or TSA. A Tscore is considered to be the midpoint of a continuous score interval from 0.5 below to 0.5 above the score. For example, a Tscore of 55 represents the midpoint of an interval from 54.5 to 55.5. Since TSA is reported to one decimal place, its interval is from .05 below to .05 above the TSA; e.g., a TSA of 57.5 represents the midpoint of an interval from 57.45 to 57.55.
To determine the percentile rank, we assume that onehalf the scores (or TSA’s) in the interval fall below the midpoint and calculate the overall percent of students that fall below the midpoint of the interval. Thus, the percentile rank for a Tscore is the percent of students below the score plus onehalf the percent of students at the score. For example, if 120 of 180 students scored below 55 and 11 of the 180 scored at 55, the percentile rank for 55 would be (120/180) + 0.5 x (11/180) = 66.6% + 3.1% = 69.7%. Percentiles are reported as integers, rounding up for decimal values of .5 or greater, so 69.7 would be rounded up to 70.
Percentiles are converted to quartiles for reporting to students on the Academic Summary as follows:
Quartile 
Description 
Percentile Ranks 
P1 
Top 25% 
75  99 
P2 
50  74 

P3 
25 – 49 

P4 
Lowest 25% 
1  24 