Simulation-based Mastery Learning Improves Cardiac
Auscultation Skills in Medical Students
John Butter, MD1,2, William C. McGaghie, PhD1, Elaine R. Cohen, BA2, Marsha E. Kaye, RN, MSN1,
and Diane B. Wayne, MD2
1Augusta Webster, MD Office of Medical Education and Faculty Development, Northwestern University Feinberg School of Medicine,
Chicago, IL, USA;2Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, USA.
BACKGROUND: Cardiac auscultation is a core clinical
skill. However, prior studies show that trainee skills are
often deficient and that clinical experience is not a
proxy for competence.
OBJECTIVE: To describe a mastery model of cardiac
auscultation education and evaluate its effectiveness in
improving bedside cardiac auscultation skills.
DESIGN: Untreated control group design with pretest
PARTICIPANTS: Third-year students who received a
cardiac auscultation curriculum and fourth year stu-
dents who did not.
INTERVENTION: A cardiac auscultation curriculum
consisting of a computer tutorial and a cardiac patient
simulator. All third-year students were required to meet
or exceed a minimum passing score (MPS) set by an
expert panel at posttest.
MEASUREMENTS: Diagnostic accuracy with simulated
heart sounds and actual patients.
RESULTS: Trained third-year students (n=77) demon-
strated significantly higher cardiac auscultation accu-
racy compared to untrained fourth year students (n=31)
in assessment of simulated heart sounds (93.8% vs.
73.9%, p<0.001) and with real patients (81.8% vs.
75.1%, p=0.003). USMLE scores correlated modestly
with a computer-based multiple choice assessment
using simulated heart sounds butnot with bedside skills
on real patients.
CONCLUSIONS: A cardiac auscultation curriculum
consisting of deliberate practice with a computer-based
tutorial and a cardiac patient simulator resulted in
improved assessment of simulated heart sounds and
more accurate examination of actual patients.
KEY WORDS: Cardiac Auscultation; simulation; medical students;
J Gen Intern Med 25(8):780–5
© Society of General Internal Medicine 2010
Clinical experience has served traditionally as a proxy for
competence in skills such as cardiac auscultation. However,
research has shown that clinical experience does not correlate
with skill in this core competency.1–4One study showed that
medical students identified only 20% of 12 cardiac events
correctly and the accuracy of residents was no better at 19%.2
Another investigation showed that except for cardiology
fellows, there was no improvement in auscultation skills after
the third-year of medical school among medical students,
residents and faculty.3The need for improved assessment
and training in core skills such as cardiac auscultation is
emphasized by the transition toward a competency based
model of medical education.5
Simulation technology with deliberate practice6can be used
to improve a variety of trainee skills. Examples include cardiac
auscultation,7,8advanced cardiac life support (ACLS),9thor-
acentesis,10and central venous catheter insertion.11–13In
addition to enhancing technical proficiency, some educational
interventions have also been shown to transfer skill to the
clinical environment and improve patient care14and patient
In an earlier study, we used an expert panel and perfor-
mance scores from a group of 100 third-year medical students
from three Chicago medical schools to set a minimum passing
score (MPS) for cardiac auscultation skills.16Setting an MPS
allows development of a mastery learning model in which all
learners achieve the desired outcome, although the time
needed to achieve mastery may vary.17,18Mastery learning, a
form of competency-based education, is a rigorous way to
document that all trainees have achieved competency in a
particular procedure or skill. The current study had two aims.
The first was to use a mastery learning program featuring
simulation technology and deliberate practice to allow third-
year medical students to meet or exceed a minimum level of
proficiency in cardiac auscultation skills during the junior
medicine clerkship. We also compared their auscultation skills
with those of fourth-year students who did not receive the
Received September 30, 2009
Revised January 21, 2010
Accepted February 10, 2010
Published online March 26, 2010
mastery learning program. The second was to determine the
impact of this intervention on the accuracy of cardiac auscul-
tation in actual patients.
This article was prepared using reporting conventions
described in the TREND Statement19for nonrandomized
Objectives and Design
The study was an untreated control group design with pretest
and posttest20of a simulation-based, mastery learning educa-
tional intervention designed to increase third-year medical
students’ clinical skills at cardiac auscultation (simulation
trained group). Primary measurements were obtained at
baseline (pretest), immediately after the educational interven-
tion in the simulation laboratory (posttest), and no longer than
two weeks following the educational intervention with actual
patients. Fourth-year medical students (traditionally trained)
did not receive the intervention and served as controls. The
cardiac auscultation proficiency of the simulation trained
group was compared with the proficiency of the traditionally
trained group to assess the impact of the intervention.
From October 2008 to April 2009, 77 third- and 31 fourth-year
students on required Department of Medicine rotations at
Northwestern Memorial Hospital (NMH) were assessed in
cardiac auscultation proficiency using a computerized multi-
ple choice case-based examination and auscultation of actual
patients. The third-year students were on the junior medicine
clerkship, an 8-week inpatient and 4-week outpatient experi-
ence. The fourth year students were on the senior medicine
clerkship, a 4-week inpatient experience. All students received
2 hours of practice with a cardiac simulator (Harvey) during
their second year of medical school. There was no other formal
cardiac auscultation training. The Northwestern University
Feinberg School of Medicine Institutional Review Board ap-
proved the study. Participants provided informed consent
before the baseline assessment.
The curriculum for third-year students featured approximately
one hour of deliberate practice of 12 major cardiac findings
(split S2, S3, S4, systolic click, innocent murmur, mitral
regurgitation, mitral stenosis, aortic regurgitation, aortic ste-
nosis, tricuspid regurgitation, continuous murmur and peri-
cardial rub). The 12 findings were selected based on results of
a previously published national survey of internal medicine
and family residency program directors.21The intervention
included a computer based, interactive self study tutorial
(UMedic)22developed at the University of Miami which features
didactic instruction, deliberate practice, and self assessment.
Students accessed this program at Northwestern’s Clinical
Education Center and used headphones to listen to the heart
sounds. The volume of the heart sounds was fixed and
students completed the tutorial at their own pace and self
reported the time spent with the tutorial.
After students spent time with the UMedic tutorial, they
received 30-40 minutes of focused review of the major cardiac
findings using a cardiac simulator (Harvey) led by an experi-
enced clinician educator (JB).
Third- and fourth-year students completed a computer-based
assessment and examined actual patients. The computerized
assessment was a set of 12 previously validated multiple-
choice questions combining a brief clinical history, vital signs,
and an audiovisual file of associated heart sounds presented
on the Harvey cardiac patient simulator.7,23,24Students chose
the best among four possible responses. There was no time
limit to complete this exercise and students could listen to the
heart sounds as many times as they wished. Third-year
students completed the computerized assessment before the
intervention (pretest) and again after the education program
(posttest). Similar to past research, the same heart sounds
were used for pretest and posttest, although presentation
order varied.7Fourth-year students completed the examina-
tion once during their clinical rotation.
At posttest, third-year students were expected to meet or
exceed the MPS of 75% set previously by a panel of 16 expert
judges.16Third-year students who did not achieve the MPS at
post-test returned for additional practice with the tutorial and
were retested until the MPS was reached.
Students also evaluated patients recruited from internal
medicine or cardiology practices based on the presence of at
least one of the 12 important cardiac findings listed above.
Students each participated in one of five assessment sessions.
Third-year students completed the assessment within 2 weeks
of the intervention. At four of the sessions students examined
four patients. At the fifth session, the students examined five
patients. Students were provided a brief clinical history and
vital signs and were asked to perform a cardiac assessment of
each patient. They had 4 minutes to perform their assessment.
Students completed a structured response form on which they
described the clinical findings (presence, absence and radia-
tion of systolic murmurs, diastolic murmurs, S3 and S4) and
chose the most likely diagnosis from the list of 12 choices.
Students received up to 12 points for each patient assessment;
11 for clinical findings and one for the final diagnosis. The
structured response form was constructed de novo for this
study at a level appropriate for third and fourth-year students.
All patients were weighted the same.
At least two board certified cardiologists, each with more
than 15 years of clinical experience and recognized for their
leadership in cardiology education, also completed a cardiac
assessment of the same patients using the same structured
response form. Their responses served as the gold standard.
Cardiologists and students were not aware of clinical diagno-
ses or echocardiogram findings of the patients. In the case of
discrepancies between cardiologists, students were given
credit for any answer provided by one of the cardiologists.
Findings by the cardiologists included mitral regurgitation,
aortic stenosis/sclerosis, tricuspid regurgitation, innocent
murmur, systolic click, S4 and a normal cardiac exam.
Third-year students completed a survey of their satisfaction
with the cardiac auscultation curriculum. United States
Medical Licensing Exam (USMLE) Step 1 scores were obtained
Butter et al.: Cardiac Auscultation Skills in Medical Students
from the registrar to assess correlations between examination
scores and cardiac auscultation performance.
reliability of the cardiologists, the preferred method for assess-
ments that depend on human judges, using Kappa (κ) coefficient
adjusted using the formula of Brennan and Prediger.25–27
When comparing the performance of third-year students
from computer-based pretest (baseline) to posttest (outcome),
within group differences were analyzed using the paired t-test.
Performance of simulation-trained third-year medical students
at computer-based posttest and patient assessments were
compared to traditionally trained fourth-year student perfor-
mance using the unpaired t-test.
Demographic data were analyzed using the chi square
statistic and t-test to assess for differences in characteristics
between the simulation-trained and traditionally trained stu-
dents. Spearman’s rho coefficient was used to assess relation-
ships between computer-based and patient assessment
performances and USMLE Step 1 scores.
Seventy-eight third-year students and 39 fourth-year students
completed required rotations in the Department of Medicine at
NMH during the study period. Seventy-seven (99%) third-year
students (simulation-trained) and 31 (79%) fourth-year stu-
dents (traditionally trained) consented to participate in the
study. As shown in Table 1, there was no significant difference
in age or USMLE Step 1 scores between groups. There were
more men in the fourth-year student group. Third-year
students spent a mean of 67.5 minutes (SD=21.5 minutes)
with the tutorial.
Some variance in the clinical findings of the expert cardiol-
ogists was expected. However, the cardiologists displayed
moderate inter-rater reliability in their patient assessments
as measured by the mean kappa coefficient (κn=0.76) of their
findings on the structured response form.
At baseline, third-year students (M=67.3%, SD=18.85)
scored similar to fourth-year students (M=73.9%, SD=14.1%)
[p=.067]. After simulation training, third-year students im-
proved their scores significantly to 93.8% (SD=11.6%) [p<
0.001] and performed better than traditionally trained fourth-
year students [p<0.001]. Four third-year students (5.2%) did
not achieve the MPS at post-test and required additional
practice. Each of these students achieved the MPS when re-
tested after less than one hour of additional self study.
Thirteen fourth-year students (41.9%) did not achieve the
MPS. There was no significant difference in performance
between males and females in the third-year student group
(94.1% vs. 93.3) [p=0.65] or the fourth-year student group
(73.8% vs. 74.3%) [p=0.93].
Table 2 displays simulated cardiac auscultation perfor-
mance by type of finding. The 12 cardiac findings are divided
into diastolic (n=4), systolic (n=6) and other (n=2). As shown,
simulation-trained third-year students outperformed fourth-
year students in identifying simulated diastolic and systolic
findings. Identification of the other two findings was similar
Using the cardiologists’ findings as a gold standard, third-
year (simulation- trained) students also more accurately
assessed patients with cardiac findings (M=81.8%, SD=8.8%)
compared to fourth-year students (M=75.1% SD 13.4%) [p=
0.003] who did not complete simulation training but had more
clinical experience. A graphic portrait of the students’ com-
puter-based and patient assessment scores is shown in the
The students’ USMLE Step 1 scores showed a modest
correlation with the multiple choice auscultation post-test (r=
0.27, p=0.002). There was no significant correlation between
USMLE scores and third or fourth-year students’ assessments
of actual patients (r=- 0.04, p=.81).
Eighty-seven percent of students completed a course eval-
uation questionnaire. Students reported that this curriculum
improved their cardiac auscultation skills, was a useful
adjunct to clinical experience and was enjoyable (Table 3).
Cardiac auscultation is a core clinical skill. Our findings show
that a curriculum featuring simulation technology and delib-
erate practice improved the ability of third-year medical
students to identify simulated heart sounds. Third-year stu-
dents also showed improved accuracy when examining actual
patients when compared to untrained fourth-year students. As
in our other mastery learning programs,9–13this intervention
featured clear goals, deliberate practice, a supportive environ-
ment and rigorous outcome measures. The computer-based
Table 1. Descriptive Statistics for n=108 Medical Students
third-year students (n=77)
fourth-year students (n=31)
USMLE Step 1 Score
% that met MPS of computer-based
assessment at posttest
Table 2. Performance of Simulated Cardiac Auscultation by Type
of Finding and Group
Butter et al.: Cardiac Auscultation Skills in Medical Students
delivery of the curriculum was especially suited to repetitive,
deliberate practice which has been shown to improve cardiac
Use of the mastery learning model allowed all third-year
students to achieve the MPS for cardiac auscultation skills
during the junior medicine clerkship. These findings advance
what is known about cardiac auscultation education for
medical students because our approach requires that all
learners meet or exceed a minimum standard. Although some
students required additional practice time, all third-year
students met or exceeded the MPS in cardiac auscultation
skills at posttest after a curriculum that was largely self-study.
Although third-year students in this study performed similarly
at baseline to another group of third-year students from three
schools,16third-year students in this study outperformed a
cohort of fourth-year students who experienced the same
medical school curriculum, but did not complete the mastery
learning program. In fact, more than 40% of the fourth-year
students failed to achieve the MPS on the computer based
examination. This reminds us that clinical experience is not a
proxy for skill29and that rigorous assessment is needed to
document the proficiency of trainees in important clinical
skills such as cardiac auscultation.
In addition to the improvements demonstrated with simu-
lated heart sounds, students who completed the mastery
learning curriculum also showed improvement in cardiac
auscultation accuracy with actual patients. The addition of
key patient data (history, vital signs) likely explains the higher
performance of subjects in this study compared to prior
studies that used cardiac auscultation findings alone.3,4,7
Although statistically significant improvements occurred both
with simulated heart sounds and with actual patients, the
improvement with actual patients was less striking than the
improvement found in the laboratory setting. This likely relates
to the observation that enhanced clinical performance (effica-
cy) is easier to detect in a controlled clinical environment than
in a patient care setting (effectiveness).30
At Northwestern, we focus on competency-based education
and patient safety and use multiple simulation-based mastery
learning programs to educate and assess trainees and meet
competency requirements. In addition to cardiac auscultation,
examples include communication skills31and invasive proce-
dures such as central venous catheter insertion,12,13and
ACLS.9Simulation-based mastery learning programs allow
trainees to take as much practice time as they need. Learners
then document skill in a simulated environment prior to actual
patient care. This approach is feasible and practical, is
compliant with competency-based accreditation requirements,
and has been shown to improve the quality of patient care
delivered by trainees in several competency areas.14,15
Medical students are expected to develop a broad range of
skills, and educators must use diverse assessments to accu-
rately evaluate their ability to function as clinicians. We found
a modest correlation between USMLE Step 1 score and student
performance on the computer-based multiple choice examina-
tion. However, there was no correlation between USMLE Step 1
score and bedside assessment of actual patients. This suggests
that the performance and interpretation of physical examina-
Figure 1. Performance of simulation-trained third-year students and
traditionally trained fourth-year students in cardiac auscultation
clinical skills assessments.
Table 3. Third-Year Student Responses to Course Evaluation Questionnaire (n=67) Likert Scale: 1= Strongly Disagree; 5= Strongly Agree
Survey itemMean (SD)
Practice with the cardiac auscultation self study tutorial boosts my cardiac auscultation skills
Educational sessions using medical simulation are fun
I receive useful educational feedback from the training sessions
The cardiac auscultation self study tutorial boosts my clinical self-confidence
Practice with cardiac auscultation self study tutorial has more educational value than patient care experience
The cardiac auscultation self study tutorial on the computer was a good use of my time
Practice with Harvey® boosts my cardiac auscultation skills
Practice with Harvey® boosts my self confidence
Practice sessions using simulation models should be a required component of clerkship education
Practice sessions using models are hard work
Increasing difficulty of simulated clinical problems helps me become a better doctor
The controlled environment in the Clinical Education Center helps me focus on clinical education problems
Clinical problems presented in the Skills Center are engaging
Combined practice with the cardiac auscultation self study tutorial and Harvey® has helped prepare me to
identify heart sounds better than clinical experience alone
Butter et al.: Cardiac Auscultation Skills in Medical Students
tion findings at the bedside represents an independent clinical
skill, distinct from the medical knowledge necessary for
success in multiple choice examinations.
This study has several limitations. First, it represents the
performance of a single group of students over a short time
period at one medical school. However, standard setting data
used to set the MPS was obtained from 100 students at three
medical schools. Second, not all cardiac diagnoses were
studied. Third, we used the clinical assessment of experienced
cardiologists and not echocardiography because there is no
gold standard for assessing cardiac physical examination
skills.32We believe this is the most appropriate reference
standard as not all valvular abnormalities produce ausculta-
tory findings and some important examination findings have
no direct echocardiographic equivalent. Fourth, we used the
UMedic self-study tutorial and Harvey cardiac patient simula-
tor for testing and education. Although Harvey is widely used
in medical education,22we do not know if use of other
modalities33would produce similar findings. Last, durability
of enhanced cardiac auscultation proficiency is unknown and
is an appropriate area for further study.
In summary, a simulation based mastery learning program
dramatically improved cardiac auscultation skills in medical
students. Skills improved in both assessments of simulated
heart sounds and examination of actual patients. The program
was rated favorably by students. Use of a mastery learning
program allows all learners to meet or exceed a predetermined
MPS and is a valuable model to achieve and document
competence in important clinical skills.
Acknowledgements: We thank the Northwestern medical students
who participated in this study for their dedication to patient care
and education. We acknowledge Drs. Douglas Vaughan and John X.
Thomas for their support and encouragement of this work. Funding
was provided through the Augusta Webster, MD Office of Medical
Education and Faculty Development. Dr. McGaghie’s contribution
was supported in part by the Jacob R. Suker, MD, professorship in
medical education at Northwestern University and by grant UL 1
RR025741 from the National Center for Research Resources,
National Institutes of Health. The National Institutes of Health had
no role in the preparation, review, or approval of the manuscript.
Funding: Office of Medical Education and Faculty Development,
Northwestern University Feinberg School of Medicine, Chicago, IL
Conflicts of interests: Dr. McGaghie has been consultant to, and
received honorariums from, the Gordon Center for Research in
Medical Education at the University of Miami Miller School of
Medicine where the "Harvey" mannequin is manufactured. None of
the other authors have conflicts of interest, financial interests or
relationships or affiliations relevant to the subject matter or
materials discussed in this manuscript.
Corresponding Author: John Butter, MD; Department of Medicine,
Northwestern University Feinberg School of Medicine, 675 N. St.
Clair Street, Suite 18-200, Chicago, IL 60611, USA (e-mail:
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