USMLE Score Interpretation Guidelines*
Description of Examinations
Step 1 assesses whether the examinee understands and can apply important concepts of the
sciences basic to the practice of medicine, with special emphasis on principles and mechanisms
underlying health, disease, and modes of therapy. Step 1 ensures mastery of not only the
sciences that provide a foundation for the safe and competent practice of medicine in the
present, but also the scientific principles required for the maintenance of competence through
lifelong learning.
Step 2 Clinical Knowledge (CK) assesses whether the examinee can apply medical knowledge,
skills, and understanding of clinical science essential for the provision of patient care under
supervision and includes emphasis on health promotion and disease prevention. Step 2 ensures
that due attention is devoted to principles of clinical sciences and basic patient-centered skills
that provide the foundation for the safe and competent practice of medicine.
Step 3 assesses whether the examinee can apply medical knowledge and understanding of
biomedical and clinical science essential for the unsupervised practice of medicine, with
emphasis on patient management in ambulatory settings. The inclusion of Step 3 in the USMLE
sequence of licensing examinations ensures that attention is devoted to the importance of
assessing the knowledge and skills of physicians who are assuming independent responsibility
for providing general medical care to patients.
Understanding Your Score
Reported scores for Step 1, Step 2 CK, and Step 3 range from 1 to 300. Small differences in
difficulty across forms and years are adjusted for using statistical procedures; thus, scores for a
given Step are comparable across years and across forms. However, it is important to note that
all USMLE examinations evolve over time in terms of test content, and that examinations taken
at two substantially different points in time may vary somewhat in terms of inclusion or
emphasis of certain content areas. USMLE stakeholders should avoid comparing scores that
were obtained at dramatically different points in time. Because the content and format of each
examination change over time, comparisons should not be made of individual scores separated
in time by more than 3-4 years. Table 1 shows the mean and standard deviation (SD) for first-
takers from US/Canadian medical schools who tested over the past 3 years.
*This is a score interpretation guide for computer-based Step 1, Step 2 CK and Step 3 examinations. The
Step 2 CS examination is reported as pass or fail only.
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Table 1. Means (SDs) First Takers from the US/Canadian medical schools
Step 1
Calendar Year
Mean (SD)
2013
228 (21)
2014
229 (20)
2015
229 (20)
Step 2 Clinical Knowledge
Academic Year
Mean (SD)
2012–2013
238 (19)
2013-2014
240 (18)
2014-2015
240 (18)
Step 3
Calendar Year
Mean (SD)
2013
222 (16)
2014
222 (16)
2015
225 (16)
The norm table (Table 2) enables you to determine the percentage of first-takers from
US/Canadian medical schools testing between January 1, 2013 and December 31, 2015 for Step
1 and Step 3 and between July 1, 2012 and June 30, 2015 for Step 2 CK who scored lower than a
given USMLE Step Examination score. For example, to compare a given score with the scores of
US/Canadian first-takers on Step 1, locate the score in the column labeled USMLE Score. Read
across the table to the percentile rank column labeled Step 1. An examinee with a Step 1 score
of 225 is at the 39
th
percentile. The 39
th
percentile means that 39% of the Step 1 first-takers
from US/Canadian medical schools in the three-year cohort described previously scored lower
than 225.
Norm tables are updated annually by dropping earlier groups of examinees and adding newer
ones. Because the data can change through this update process, you should use the most
recent norm table available on the USMLE website to obtain percentile ranks. Using the most
recent norm table avoids confusion and ensures that everyone is viewing the same, current
data.
Although percentile ranks for Step 1, Step 2 CK, and Step 3 are shown in the same norm table, it
is important to note that scores on the three Steps are not directly comparable. For example, a
score of 220 on Step 1 is not equivalent to a score of 220 on Step 2 CK or on Step 3. A
comparison of scores across Steps is not appropriate.
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Passing Scores
A pass or fail result is provided, as a USMLE recommendation, for each exam administration.
Passing results are based on achievement of specified levels of proficiency established prior to
administration of examinations. Statistical procedures are employed to ensure the level of
proficiency required to pass remains uniform across forms of the examination. As noted in the
USMLE Bulletin of Information, the score required to meet the recommended level of
proficiency is reviewed periodically and may be adjusted without prior notice. Notice of
adjustments is posted in the Announcements section of the USMLE website. Information about
the current minimum passing scores is available at http://www.usmle.org/transcripts/ and
information about passing rates is available at http://www.usmle.org/performance-data/.
Precision of Scores
Measurement error is present on all tests, and the standard error of measurement (SEM)
provides an index of the imprecision of scores. Using the SEM, it is possible to calculate a score
interval that indicates how much a score might vary across repeated testing using different sets
of items covering similar content. Plus and minus one SEM represents an interval that will
encompass about two thirds of the observed scores for an examinee’s given true score.
Currently, the SEM is approximately 5 for Step 1 and 6 points for Steps 2CK and 3.
The standard error of difference (SED) in scores is an index used to assess whether the
difference between two scores is statistically meaningful. If the scores received by two
examinees differ by two or more SEDs, it is likely that the examinees are different in their
proficiency. Currently, the SED is approximately 8 points for Step 1 and Step 3, and 9 points for
Step 2CK.
Guidelines for Use of USMLE Step Scores for Selection Decisions
When comparing examinee performance, it is generally appropriate to consider Step
examination scores in conjunction with other criteria such as course grades and faculty
evaluations, rather than using test scores as the sole basis for decisions. Test scores should be
viewed as approximate rather than exact measures of medical knowledge. Small differences in
Step examination scores alone should not be used as the basis for selection decisions about
examinees, and scores that are relatively old may not accurately reflect current knowledge and
ability.
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