; Published online before print June 6, 2012;
Jeffrey H. Barsuk, Elaine R. Cohen, Timothy Caprio, et al.
residents' lumbar puncture skills
Simulation-based education with mastery learning improves
June 11, 2012 This information is current as of
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® is the official journal of the American Academy of Neurology. Published continuously
Simulation-based education with mastery
learning improves residents’ lumbar
Jeffrey H. Barsuk, MD,
Elaine R. Cohen, MEd
Timothy Caprio, MD
William C. McGaghie,
Tanya Simuni, MD
Diane B. Wayne, MD
Objective: To evaluate the effect of simulation-based mastery learning (SBML) on internal medi-
cine residents’ lumbar puncture (LP) skills, assess neurology residents’ acquired LP skills from
traditional clinical education, and compare the results of SBML to traditional clinical education.
Methods: This study was a pretest-posttest design with a comparison group. Fifty-eight post-
graduate year (PGY) 1 internal medicine residents received an SBML intervention in LP. Residents
completed a baseline skill assessment (pretest) using a 21-item LP checklist. After a 3-hour
session featuring deliberate practice and feedback, residents completed a posttest and were
expected to meet or exceed a minimum passing score (MPS) set by an expert panel. Simulator-
trained residents’ pretest and posttest scores were compared to assess the impact of the inter-
vention. Thirty-six PGY2, 3, and 4 neurology residents from 3 medical centers completed the
same simulated LP assessment without SBML. SBML posttest scores were compared to neurol-
ogy residents’ baseline scores.
Results: PGY1 internal medicine residents improved from a mean of 46.3% to 95.7% after SBML
(p ? 0.001) and all met the MPS at final posttest. The performance of traditionally trained neurol-
ogy residents was significantly lower than simulator-trained residents (mean 65.4%, p ? 0.001)
and only 6% met the MPS.
Conclusions: Residents who completed SBML showed significant improvement in LP procedural
skills. Few neurology residents were competent to perform a simulated LP despite clinical experi-
ence with the procedure. Neurology®2012;79:1–1
LP ? lumbar puncture; MPS ? minimum passing score; PGY ? postgraduate year; SBML ? simulation-based mastery learning.
Lumbar puncture (LP) is commonly performed by physicians-in-training who often learn
vicariously by observing procedures performed by peers. This method leads to uneven skill
acquisition and trainee discomfort.1
The American Board of Psychiatry and Neurology,2the American Association of Neurol-
ogy,3and the Accreditation Council for Graduate Medical Education4have no formal policies
to ensure the competence of neurology residents at performing LP. The American Board of
Internal Medicine does not require procedural competence in LP, but advises use of simulation
training before procedures are performed on patients.5Despite this, many residents will ulti-
mately practice in a setting where competence in LP is required.
Simulation technology increases procedural skill by providing the opportunity for deliberate
practice in a safe environment.6Researchers at Northwestern University use simulation-based
education to train medical residents to mastery skill levels in procedures such as central venous
catheter insertion,7–9thoracentesis,10and advanced cardiac life support.11Mastery learning is a
stringent form of competency-based education that requires trainees to acquire clinical skill mea-
From the Department of Medicine (J.H.B., E.R.C., T.C., D.B.W.), Center for Education in Medicine (W.C.M.), and Department of Neurology
(T.S.), Northwestern University Feinberg School of Medicine, Chicago, IL.
Study funding: The research was funded through the Excellence in Academic Medicine Act by the Illinois Department of Healthcare and Family
Services. Dr. McGaghie’s contribution was supported in part by the Jacob R. Suker, MD, professorship in medical education and by grant UL 1 RR
025741 from the National Center for Research Resources, NIH. The NIH had no role in the preparation, review, or approval of the manuscript.
Go to Neurology.org for full disclosures. Disclosures deemed relevant by the authors, if any, are provided at the end of this article.
Correspondence & reprint
requests to Dr. Barsuk:
Copyright © 2012 by AAN Enterprises, Inc.
Published Ahead of Print on June 6, 2012 as 10.1212/WNL.0b013e31825dd39d
sured against a fixed achievement standard.12In
mastery learning, educational practice time var-
ies but results are uniform. This approach im-
proves patient care outcomes13,14and is more
effective than clinical training alone.15
The current study had 3 aims: first, to eval-
uate the impact of a simulation-based mastery
learning (SBML) intervention on internal
medicine residents’ LP skills; second, to assess
neurology residents’ acquired LP skills from
traditional clinical education; third, to com-
pare the results of SBML with traditional clin-
ical education for LP skill acquisition.
METHODS Design. This was a pretest-posttest design with
a comparison group16of an SBML intervention in LP perfor-
mance. Postgraduate year (PGY) 1 internal medicine residents
who received the intervention were compared to PGY2–4 neu-
rology residents who received clinical training alone. Interven-
tion group (simulator-trained) internal medicine residents
underwent a pretest in LP clinical skills using a simulator, com-
pleted an SBML educational intervention, and a skills posttest.
PGY2–4 neurology residents (traditionally trained) completed
an LP clinical skills examination (baseline test) and served as a
comparison group (figure 1). The definition of traditional train-
ing was conventional clinical neurology residency education at
Setting and participants. Intervention group participants
were all PGY1 internal medicine residents (n ? 58) at North-
western University from July–September 2010. PGY2–4 neu-
rology residents (n ? 49) at 3 university-affiliated academic
centers in Chicago, IL, were eligible to serve as the traditionally
trained comparison group. Neurology residents from North-
western University were not eligible to participate in the study
because they previously received simulation-based education in
LP. Participating neurology residents underwent baseline testing
from December 2010 to June 2011.
Standard protocol approvals, registrations, and patient
consents. The Northwestern University Institutional Review
Board approved the study, and all participants provided in-
formed consent before participating.
Procedure. This study was conducted using an LP simulator
from Kyoto Kagaku (Torrance, CA) which costs approxi-
mately $2,000.17This LP simulator represents a patient’s
lower torso and resembles lumbar spinal anatomy closely. The
skin and tissues provide life-like resistance to a spinal needle,
and allow trainees to measure an opening pressure and collect
CSF (figure 2).
Simulator-trained PGY1 internal medicine residents under-
went a clinical skills examination using a 21-item LP perfor-
mance checklist (pretest). Subsequently, they completed a
3-hour education session featuring the New England Journal of
Medicine video on LP,18an interactive LP demonstration, and
deliberate practice with directed feedback.19All participants were
required to complete the educational program regardless of pre-
test performance. A senior faculty member (J.H.B.) with exper-
tise in SBML and LP supervised all sessions. Immediately after
the educational intervention, simulator-trained residents were
required to meet or exceed a minimum passing score (MPS) on a
clinical skills examination (posttest) using the checklist. Resi-
dents who did not achieve the MPS engaged in more deliberate
practice and were retested until the MPS was reached—the key
feature of mastery learning.12Traditionally trained PGY2–4
neurology residents completed a baseline test in LP using the
simulator and 21-item checklist. All skills examinations were
video recorded. Residents were blind to individual items on the
checklist during testing and training sessions.
Measurement. We developed the 21-item LP checklist using
relevant sources18,20and rigorous step-by-step methods.7–11,21,22
Each skill or action was listed in order and given equal weight
using a dichotomous scoring system (done correctly or incor-
rectly). The checklist was designed by 1 author with expertise in
LP (J.H.B.) and reviewed for completeness and accuracy by 3
authors with expertise in LP, simulation-based education, and
checklist design (T.S., E.R.C., D.B.W.). We pilot tested the
checklist on a group of 5 medical educators who were not study
subjects to estimate reliability and face validity. The final check-
list was a consensus between authors.
A multidisciplinary panel of 10 clinical experts determined
the MPS using the Angoff (item-based) and Hofstee (group-
based) standard setting methods.23,24The panel was composed of
Northwestern University faculty members board certified in
neurology (n ? 2), anesthesiology (n ? 2), emergency medicine
(n ? 3), and internal medicine (n ? 3). Each panelist received
instruction in standard setting and used the Angoff and Hofstee
methods to assign pass/fail standards. The mean of the Angoff
and Hofstee scores was used as the final MPS.24
A second rater rescored a 50% random sample of video re-
corded clinical skills examinations using the 21-item checklist to
Figure 1 Flow diagram of study design
PGY ? postgraduate year.
Neurology 79July 10, 2012
assess inter-rater reliability. This examiner was blind to examinee
group assignment, pre/posttest status, and the aims of the study.
Participants provided demographic data including age,
gender, training program affiliation, and year of training.
Each resident assessed procedural confidence on a self-rating
scale (0 ? not confident to 100 ? very confident) and pro-
vided information about experience performing LP (number
of procedures performed in actual clinical care).
Primary outcome measures were performance of simulator-
trained and traditionally trained residents on the clinical skills
examinations. Secondary outcome measures were correlations
between clinical skills examination performance and resident de-
mographics including year of training, self-confidence, and prior
Data analysis. Checklist score reliability was estimated by cal-
culating interrater reliability using the mean kappa coefficient
across all checklist items. Internal medicine residents’ mean pre-
and posttest checklist scores were compared using a paired t test.
Mean internal medicine posttest scores were compared to mean
neurology baseline scores using the independent t test. ?2tests
were used to compare individual checklist items between the 2
groups. Multiple linear regression was used to evaluate between
group differences in posttest (internal medicine) and baseline test
scores (neurology) while controlling for age, gender, year of
training, self-confidence, and LP procedure experience. Multiple
linear regression was also used to assess relationships within
groups. In simulator-trained internal medicine residents, we
measured associations between posttest clinical skills examina-
tion performance and age, gender, reported self-confidence, LP
procedure experience, and pretest performance. In the tradition-
ally trained neurology residents, we measured associations be-
tween baseline clinical skills examination performance and age,
gender, year of training, institution affiliation, reported self-
confidence, and LP procedure experience.
RESULTS All 58 internal medicine residents partic-
ipated in the study and completed the entire proto-
col. Thirty-six of 49 (74%) eligible neurology
residents participated in the study and completed the
entire protocol. The other 26% did not participate
due to scheduling difficulties. Fourteen PGY2, 11
PGY3, and 11 PGY4 neurology residents enrolled in
the study. Table 1 shows baseline demographics of all
Interrater reliability was high across the 21 check-
list items (?n? 0.75). The expert panel set the MPS
used in the clinical skills examination at 85%. One of
58 (2%) PGY1 internal medicine residents met the
MPS at pretest. Fifty-five of 58 (95%) met the MPS
at posttest after the 3-hour intervention. The 3
PGY1 residents who did not meet the MPS at imme-
diate posttest subsequently reached the MPS within
1 hour of further training. In the traditionally trained
group of PGY2–4 neurology residents, 2 of 36 (6%)
met or exceeded the MPS at baseline testing. Figure 3
Figure 2Lumbar puncture (LP) simulator
Table 1Baseline demographics of simulator-trained and traditionally trained residents
residents (n ? 58)
PGY2–4 traditionally trained
neurology residents (n ? 36)p Value
Mean ? SD age, y
26.9 ? 1.930.4 ? 3.9
No. of LPs performed in actual clinical
care, mean ? SD
1.0 ? 1.7 25.4 ? 23.9
Self-confidence regarding ability to perform
LP (scale 0 ? not confident, 100 ? very
confident), mean ? SD
42.6 ? 27.7 74.0 ? 16.5
Abbreviations: LP ? lumbar puncture; PGY ? postgraduate year.
Neurology 79 July 10, 2012
is a graphic portrayal of internal medicine and neu-
rology residents’ clinical examination scores.
Simulator-trained residents showed a highly sig-
nificant 107% pretest-to-posttest gain as cohort
checklist performance mean scores increased from
46.3% (SD ? 17.4) to 95.7% (SD ? 4.9; p ?
0.001). Traditionally trained neurology residents
scored a mean of 65.4% (SD ? 14.2) on the check-
list. Posttest scores of simulator-trained internal
medicine residents were 46% higher than scores of
traditionally trained neurology residents (p ? 0.001).
Results remained significant after controlling for age,
gender, year of training, self-confidence, and LP pro-
cedural experience (p ? 0.001). At the individual
item level, simulator-trained residents displayed sig-
nificantly higher skill on 18 of the 21 items on the
LP checklist (table 2).
Regression analysis also showed no relationship
within groups between clinical skills examination
performance and age, gender, year of training, insti-
tution affiliation, reported self-confidence, and LP
DISCUSSION Use of SBML featuring an opportu-
nity for deliberate practice and feedback produced a
large and consistent skill improvement and almost
eliminated performance variability among residents.
By contrast, neurology residents from 3 Chicago aca-
demic institutions demonstrated poor procedural
skill despite standard residency training and substan-
tial experience with actual LPs. Surprisingly, more
than half of neurology residents did not correctly
identify the anatomic location for an LP and were
unable to list routine tests ordered on CSF. These
results illustrate the limitations of traditional clinical
training and suggest a role for simulation training
during neurology residency.
This study contributes to knowledge about proce-
dural skill acquisition among medical trainees. There
was no association between resident demographic
variables such as age, gender, institution, and year of
training and LP procedural skill. Within-group self-
confidence and number of LP procedures performed
in actual clinical care also did not correlate with mea-
sured procedural skill. This confirms results of stud-
ies of other medical procedures where trainee clinical
experience did not predict procedural skill.7–10,21In
an earlier study of 501 LPs, a surrogate for proce-
dural skill (incidence of post LP headache) was not
related to the number of years in practice or training
level of the clinician who performed the procedure.25
This consistent finding is a reminder that clinical ex-
perience alone is not a proxy for skill26and that pro-
Figure 3Clinical skills examination (checklist) performance
Clinical skills examination (checklist) pre- and final posttest performance of 58 first-year simulator-trained internal medi-
cine residents and baseline performance of 36 traditionally trained neurology residents. Three internal medicine residents
failed to meet the minimum passing score (MPS) at initial post-testing. PGY ? postgraduate year.
Neurology 79 July 10, 2012
cedural competence should only be assessed using
reliable methods involving simulation or clinical
A recently published article calls for additional ed-
ucational research in neurology.27Our study evalu-
ated the effect of simulation-based education with
mastery learning for resident education using rigor-
ous assessment standards. Earlier studies used simula-
tion to evaluate LP skills of internal medicine,28
emergency medicine,29and pediatric residents,30but
mastery standards were not imposed. Use of the mas-
tery model improves clinical care in advanced cardiac
life support13and central venous catheter insertion.14
Further study is required on the effect of SBML on
neurology resident education.
This study has several limitations. First, the study
enrolled a relatively small group of trainees although
they represent multiple training programs. Second,
we used the LP model for both education and test-
ing, potentially confounding the improvement in
posttest scores. However, this does not diminish the
pronounced impact simulation-based training had
on LP skills. Third, only 74% of neurology residents
at the 3 institutions participated, and neurology resi-
dents did not complete simulation-based education.
We have no reason to believe our results would be
different if the entire cohort of neurology residents
participated in the educational intervention. Fourth,
posttesting occurred immediately after training po-
tentially enhancing recall of the procedure. Further
study is required to address long-term retention of
LP skills. We previously showed that simulation-
based education for central venous catheter insertion
and advanced cardiac life support is associated with
significant skills retention 1 year after training.31,32
Finally, in service of translational science goals33we
have not yet linked improved LP skills in the simu-
lated environment to improved clinical health care
delivery practices and better patient outcomes.
This study demonstrates that simulation-based
education boosts LP skills beyond traditional train-
ing methods. Few neurology residents in our study
were competent to perform a simulated LP despite
substantial clinical experience with the procedure.
Residents who completed simulation-based educa-
tion displayed better procedural skills despite signifi-
cantly less clinical experience with the procedure. In
light of these results, we believe a procedural stan-
dard should be set and documented for all residents
prior to performing an LP in actual clinical care.
J. Barsuk was involved in study concept and design, collecting data, statis-
tical analysis and interpretation of data, study supervision, and drafting
and revising the manuscript. E. Cohen was involved in study concept and
design, collecting data, statistical analysis and interpretation of data, study
supervision, and drafting and revising the manuscript. T. Caprio was in-
volved in collecting and interpreting study data, and revising the manu-
script. W. McGaghie was involved in study concept and design, statistical
analysis and interpretation of data, study supervision, and revising the
manuscript. T. Simuni was involved in study concept and design, inter-
pretation of data, and revising the manuscript. D. Wayne was involved in
study concept and design, statistical analysis and interpretation of data,
study supervision, obtaining funding, and revising the manuscript.
The authors thank the Northwestern University internal medicine resi-
dents and participating Chicago neurology residency programs for their
dedication to education and patient care and Drs. Douglas Vaughan and
Mark Williams for their support and encouragement of this work.
Table 2Lumbar puncture skills checklist and percentage of traditionally
trained neurology and simulator-trained internal medicine
residents who completed each item correctly
Checklist skill item
(n ? 58), n (%)
(n ? 36), n (%)p Value
Informed consent obtained
51 (87.9)15 (41.7)
52 (87.9)13 (36.1)
Call “time out”
56 (96.6) 6 (16.7)
Properly position the patient
57 (98.3)30 (83.3)0.007
Demonstrate knowledge of correct
anatomic location for procedure
52 (89.7)17 (47.2)
Put on sterile gloves
58 (100)33 (91.7)0.025
Properly set up equipment
56 (96.6)19 (52.8)
Clean the skin with Betadine ? 3
(do not use chlorhexidine)
56 (96.6)25 (69.4)
Drape the patient
57 (98.3) 36 (100) 0.43
Use 1% lidocaine to form a wheal at
55 (94.8)23 (63.9)
Anesthetize deeper structures
54 (93.1) 23 (63.9)
Insert spinal needle advancing
58 (100)30 (83.3)0.001
Bevel must be in correct direction
57 (98.3) 30 (83.3)0.007
Slowly advance the needle with
periodic checking for CSF (removal
of stylet) until space entered
54 (93.1)27 (75.0)0.013
Measure opening pressure
56 (96.6)23 (63.9)
Collect fluid in proper tubes
55 (94.8)28 (77.8)0.012
Remove the needle after the stylet
50 (86.2)30 (83.3)0.70
54 (93.1)32 (88.9)0.48
Notify the nurse the procedure is
done; give postprocedure orders
55 (96.5)13 (36.1)
List routine tests to be ordered (must
include glucose, cell count, protein,
Gram stain, culture)
52 (89.7)15 (41.7)
Maintain sterile technique
53 (93.0)27 (75.0)0.015
Abbreviations: Abbreviation: PGY ? postgraduate year.
Neurology 79July 10, 2012
The authors report no disclosures relevant to the manuscript. Go to
Neurology.org for full disclosures.
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Neurology 79 July 10, 2012
DOI 10.1212/WNL.0b013e31825dd39d Download full-text
; Published online before print June 6, 2012;
Jeffrey H. Barsuk, Elaine R. Cohen, Timothy Caprio, et al.
Simulation-based education with mastery learning improves residents' lumbar
June 11, 2012 This information is current as of
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