Continuous versus step by step training for learning surgical anatomy on an open inguinal hernia model

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097
Citation: Nazari T, Zeb MH, Dankbaar MEW, Lange JF, van Merriënboer JJG, et al. (2019) Continuous versus step by step training for learning surgical anatomy on
an open inguinal hernia model. J Surg Surgical Res 5(2): 097-102. DOI: https://dx.doi.org/10.17352/2455-2968.000082
https://dx.doi.org/10.17352/jssr DOI:
2455-2968
ISSN:
CLINICAL GROUP
Abstract
Background: Segmentation of surgical procedures may facilitate learning. The step-by-step framework
segments surgical procedures in a standardized manner based on anatomy. The effects of the framework
are compared to a continuous approach, on learning anatomy on an inguinal hernia model by pre-novices.
Methods: Students from 10 high schools located in or near Rochester, Minnesota, were randomized
into continuous and step-by-step groups. They trained using step-by-step versus continuous video-
demonstrations of an open inguinal hernia repair on a simulation model. Anatomical knowledge and
cognitive load were assessed.
Results: In total, 220 students participated (156 female; mean age 15 years). In the selection that
watched the video-demonstration, the step-by-step group answered 1.9 questions correctly, and the
continuous group 2.4, p=0.010. The cognitive load did not differ between the groups.
Conclusions: In pre-novices, anatomy knowledge transfer might be better using continuous rather than
step-by-step video-demonstrations.
Research Article
Continuous versus step by step
training for learning surgical anatomy
on an open inguinal hernia model
Tahmina Nazari1*, Muhammad
H Zeb2, Mary EW Dankbaar3,4,
Johan F Lange1,5, Jeroen JG van
Merriënboer6, Theo Wiggers7 and
David R Farley2
1Department of Surgery, Erasmus University Medical
Center, Rotterdam, The Netherlands
2Department of Surgery, Mayo Clinic, 200 First Street
Southwest, Rochester, MN 55905, USA
3The Institute of Medical Education Research
Rotterdam (iMERR), The Netherlands
4Department of Education, Erasmus University
Medical Center, Rotterdam, The Netherlands
5Department of Surgery, IJsselland Hospital, Capelle
aan den IJssel, The Netherlands
6Department of Educational Development and
Research, Faculty of Health, Medicine & Life Sciences
Maastricht University, Maastricht, The Netherlands
7Incision Academy, Mauritskade 63, Amsterdam, The
Netherlands
Received: 05 November, 2019
Accepted: 30 November, 2019
Published: 02 December, 2019
*Corresponding author: Tahmina Nazari, MD, Depart-
ment of Surgery, Erasmus University Medical Center,
Doctor Molewaterplein, 40, 3015, GD Rotterdam, The
Netherlands, E-mail:
Keywords: Segmentation; Step-by-step framework;
Stepwise; Cognitive load; Anatomy knowledge
https://www.peertechz.com
Abbreviations
CPR: Cardiopulmonary Resuscitation; IBM: International
Business Machines
Introduction
To prepare for a surgical procedure, learners may use many
resources (journals, books, video, et cetera) including learning
from their superiors by watching them perform the surgery in
the operating room, known as the master-apprentice model [1].
Due to work hour regulations and decreased exposure time in
the operating room, the emphasis today in surgical education
is on better preparation before entering the operating room
[2,3]. A framework based on anatomical structures has been
proposed by our group to segment surgical procedures into
steps in a standardized manner [4]. An international expert
panel supported the preciseness, usefulness, and applicability
of the step-by-step framework. We pondered that the step-
by-step framework may also facilitate surgical training for
anatomical knowledge using the video-demonstration of a
surgical procedure.
The process of learning and the effectiveness of instructional
design choices should be understood to optimize the teaching
process. The cognitive theory of multimedia learning can
explain the learning process from dynamic visualizations such
as video and animation [5]. An assumption in this theory is that
learners have a limited cognitive capacity available to process
new information [6].
The cognitive capacity needed to process new information
is known as cognitive load [7]. When this new information is
presented as a video or animation (streaming information),
the cognitive load can be high because information that
is disappearing from the screen needs to be retained and
processed in working memory, or otherwise information that
is later presented on the screen cannot be understood (also
called transiency of information).

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https://www.peertechz.com/journals/journal-of-surgery-and-surgical-research
Citation: Nazari T, Zeb MH, Dankbaar MEW, Lange JF, van Merriënboer JJG, et al. (2019) Continuous versus step by step training for learning surgical anatomy on
an open inguinal hernia model. J Surg Surgical Res 5(2): 097-0102. DOI: https://dx.doi.org/10.17352/2455-2968.000082
To lower the cognitive load, the segmentation principle
in the cognitive theory of multimedia learning can be applied
[8]. With the segmentation principle, the video is divided
into smaller parts with pauses in between, allowing learners
to completely process one segment before moving on to
the following segment. Segmentation could also lower the
cognitive load by constructing a cognitive schema of the task
[9]. The construction of cognitive schemas is especially useful
for novices as they do not possess the schemas to comprehend
a complex task yet [8].
In the surgical fi eld, the effects of the step-by-step
framework on learning surgical anatomy have not been proven.
The current study aimed to investigate the effects of an online
course based on the step-by-step framework, consisting of a
video-demonstration and textual description of the knowledge
of the surgical anatomy of a surgical procedure in pre-novices,
such as high school students. The primary endpoints are
anatomical knowledge and cognitive load.
Materials and Methods
Design
It was a randomized study with two groups: an online
course containing continuous video-demonstration and textual
description (continuous group) and an online course containing
segmented video-demonstration and textual description
(step-by-step group). Random assignment to one of the two
groups was realized on the school level in which all students
of each participating school were included within the same
group to prevent contamination. This cluster randomization
was chosen as students from the same classes, and teachers
cannot be randomized on an individual basis as there is too
much risk of contamination. The risk of cluster randomization
is an imbalance between the groups, a recruitment bias, such as
different teachers, different amounts of attention to the study,
etcetera. This problem has been addressed by a large sample
size [10]. The randomization was blinded for the researchers.
The open inguinal hernia repair was chosen as a surgical
example for the study since this procedure is complicated and
execution cannot be performed without adequate anatomical
knowledge. One week before the test, the high school students
were granted access to their group-specifi c online course to
prepare for the test. During the test day, the students fi lled
in a questionnaire and were examined on their anatomical
knowledge using a simulation model representing all relevant
anatomical structures. Figure 1 outlines the study design.
Participants
The participants were 220 high school students (64 male
and 156 female) from 10 high schools in or near Rochester,
Minnesota, in the United States. The participants’ average age
was 15 years (SD ±2, range 12 to 18) with a median grade of 11
(range 7th to 12th grade).
The study took place within the Mayo Clinic in Rochester,
Minnesota, as part of a more extensive seminar involving
other medical learning experiences (The “Saving Lives with
Gus” seminar offered exposure to CPR, using a defi brillator,
tying surgical knots, using an ultrasound machine, et cetera.)
Participation was voluntary and all participants consented to
the study.
Materials
Online course
One week before the seminar, the students could access
an online course where they were instructed to study
a surgical procedure (open inguinal hernia repair) and
ConƟnuous
video & text
ConƟnuous
Group
Step-by-step
Group
QuesƟonnaire
demographics
and
cognŝƟve load
Anatomy
knowledge
test
IntroduĐƟon
video & text
Segmented
video & text
Online course Test day
Figure 1: Study design.
Figure 2: Open inguinal hernia simulation model.
anatomy (male groin). The students had one week to study
the course. The course consisted of an introduction and the
video-demonstration and textual description of the open
inguinal hernia repair including all the anatomical terms. The
difference between the two groups was the continuous video-
demonstration and textual description versus a step-by-step
video-demonstration and textual description of the surgical
procedure. The rest of the course, including the information
about anatomy, was identical.
The introduction contained a text and a video of 2:39
minutes, which explained an inguinal hernia. The text also
explained a hernia and medical jargon such as medial and
lateral. The introduction was similar for both groups.
The video demonstrated surgery on an open inguinal hernia
simulation model of a male patient. The simulation model
mimicked the abdominal wall as each felt layer corresponded
with an abdominal wall layer, for example, Camper’s fascia,
Scarpa’s fascia, external oblique aponeurosis, internal oblique
muscle and transversalis fascia. In the video-demonstration,
all the encountered anatomical structures were emphasized.
These structures were mentioned by the voice-over, shown
by highlighting the structure and were named on the screen

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https://www.peertechz.com/journals/journal-of-surgery-and-surgical-research
Citation: Nazari T, Zeb MH, Dankbaar MEW, Lange JF, van Merriënboer JJG, et al. (2019) Continuous versus step by step training for learning surgical anatomy on
an open inguinal hernia model. J Surg Surgical Res 5(2): 097-0102. DOI: https://dx.doi.org/10.17352/2455-2968.000082
(Figure 2). The simulation model was used to create a realistic
environment for the student in order to motivate them.
The continuous group accessed the online course containing
the introduction and on a separate page the continuous video-
demonstration of the open inguinal hernia repair (10:56
minutes). The continuous textual description was below the
video. The step-by-step group reached the online course
containing the identical introduction as the continuous group.
On a separate page were the step-by-step video-demonstration
of the open inguinal hernia repair and textual description. For
the step-by-step group, the video was 11:14 minutes in length;
six segmented surgical steps, and title frames with the name
of the step of 3 seconds before each step. Below the video
was the step-by-step textual description in table-form with
steps, substeps, and the actions. Each substep, a combination
of an anatomical structure and an action, had its explanation
[4]. This information was the same as the information for
the continuous group but formally structured. Both groups
could view the video-demonstration and textual description
simultaneously. The videos could be watched as often as
wanted and could be paused whenever the participant desired.
Questionnaire
The high school students were asked to fi ll in a questionnaire
regarding their time spent studying the online course and how
they perceived their cognitive load during the online course
(Appendix A). The questionnaire also inquired if the teacher
had discussed the course in class, and if so, how many hours.
The cognitive load during preparation was measured using
a shortened rating scale of Leppink [11]. The questionnaire
included four statements concerning cognitive load (Table 1).
Each statement was scored on a 10-point Likert scale, ranging
from 0 “not at all” to 10 “completely”.
Anatomy knowledge test
The learning outcomes were assessed using an anatomy
knowledge test in which the students had to recognize the
correct anatomical structures in the simulation model.
During the exam, the high school students received a list of
8 anatomical structure names that had to be linked to the 6
questioned anatomical structures in the simulation model
(Table 2). The maximum score was 6 correct answers. The
simulation model used during the experiment was identical to
the model used in the video-demonstration during the online
course.
Statistical analysis
All statistical analyses were done with SPSS (IBM Corp.
Released 2016. IBM SPSS Statistics for Windows, Version 24.0.
Armonk, NY: IBM Corp.). The dependent variables were the
number of correct answers on the anatomy knowledge test and
the scores on the modifi ed cognitive load questionnaire. The
independent variable was the type of online course; continuous
or segmented based on the step-by-step framework. The Chi-
square test or the Mann Whitney U test, was used to compare
the groups. The internal consistency for the cognitive load was
determined using Cronbach’s . P-values of less than 0.05
were considered statistically signifi cant.
Results
A total of 220 high school students from ten high schools
participated. The continuous group consisted of 108 students
with 85 females (78.7%) and an average age of 17 years (range
15-18). The step-by-step group (n=112) consisted of 71 females
(63.4%) with an average age of 14 years (range 12-18) (Figure
Table 1: Shortened cognitive load rating.
Continuous
group
Step-by-
step group
Statistical analysis
(Mann-Whitney U)
Mean±SD Mean±SD U p-value
The content of this activity was very
complex. 5.3±2.2 5.4±2.1 5402.5 0.801
In this activity, complex terms were
mentioned. 6.1±2.5 6.2±2.4 5387 0.775
I invested a high mental effort in this
activity. 6.0±2.5 5.7±2.6 5064.5 0.306
This activity really enhanced my
understanding of the content that was
covered.
6.5±2.4 6.7±2.6 5104.5 0.350
Total rating cognitive load 6.0±1.9 6.0±1.7 5503 0.984
Table 2: Eight anatomical structures within the open inguinal hernia simulation
model.
1. Skin
2. Camper’s fascia
3. Scarpa’s fascia
4. External oblique aponeurosis
5. Internal oblique muscle
6. Spermatic cord
7. Inguinal ligament
8. Transversalis fascia
Figure 3: Age distribution.

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Citation: Nazari T, Zeb MH, Dankbaar MEW, Lange JF, van Merriënboer JJG, et al. (2019) Continuous versus step by step training for learning surgical anatomy on
an open inguinal hernia model. J Surg Surgical Res 5(2): 097-0102. DOI: https://dx.doi.org/10.17352/2455-2968.000082
3). More students in the step-by-step group watched the
introduction video regarding the open inguinal hernia repair
(p=0.002), while more students in the continuous group
watched the video-demonstration (p=0.006). There was no
difference in study time on the website, additional lessons of
the high school teacher, or explanation time of the high school
teacher (Table 3).
In the complete selection (n=220), the continuous group
had an average of 2.1 answers correct (±SD 1.2) out of the 6
anatomy knowledge questions compared to 1.7 in the step-
by-step group (±SD 1.3), U=4826, p=0.008 (Table 4). Variables
that had a signifi cant effect on the number of correct answers
on the anatomy knowledge test were watching the video-
demonstration (U=3916, p<0.001), age (p=0.017) and additional
lessons of the high school teachers (U=2857, p=0.004).
As shown in Table 4, independent of the intervention, the
students that watched the video-demonstration answered 2.2
anatomy knowledge test questions correctly in comparison
Table 3: Preparation.
Continuous group (n=108) Step-by-step group (n=112) p-value
Gender Female (n) 85 (78.7%) 71 (63.4%)
Male (n) 23 (21.3%) 41 (36.6%) 0.012^*
Age in years (median; range) 17 (15-18) 13 (12-18) <0.001†*
Watched introduction video Yes (n) 86 (79.6%) 105 (93.8%) 0.002^*
Watched video-demonstration Yes (n) 71 (65.7%) 53 (47.3%) 0.006^*
Study time on website (n) 0 hours 1 (0.9%) 1 (0.9%) 0.734^
0-1 hour 101 (93.5%) 102 (91.1%)
1-2 hour 6 (5.6%) 7 (6.3%)
2-3 hour 0 (0%) 1 (0.9%)
≧ 4 hours 0 (0%) 1 (0.9%)
Additional lessons of high school teacher (n) Yes 21 (19.4%) 24 (21.4%) 0.715^
Explanation time high school teacher (n) 0 hours 88 (81.5%) 90 (80.4%) 0.132^
0-1 hour 20 (18.5%) 18 (16.1%)
1-2 hour 0 (0%) 4 (3.6%)
^ analyzed using Chi square test; † analyzed using Mann-Whitney U test; * statistically signifi cant.
Table 4: Comparison of the students that watched the video-demonstration versus that did not watch the video-demonstration within the continuous and the step-by-step
group.
Continuous group (n=108) Step-by-step group (n=112)
Watched video-
demonstration
Not watched video-
demonstration
Statistical
analysis
Watched video-
demonstration
Not watched video-
demonstration
Statistical
analysis
Total participants (n) 71 37 53 59
Gender Female (n) 54 31 p=0.352^ 35 36 p=0.582^
Male (n) 17 6 18 23
Age (mean; in years) 17 17 U=1096
p=0.127φ14 14 U=1432
p=0.432φ
Additional lessons of
high school teacher
Yes (n) 17 4 p=0.102^ 18 6 p=0.002^*
No (n) 54 33 35 53
Explanation time high
school teacher
0 hours (n) 53 35
p=0.011^*
35 55
p=0.001^*0-1 hour (n) 18 2 14 4
1-2 hour (n) 0 0 4 0
Number of correct answers (mean) 2.4±1.0 1.5±1.5 U=788
p<0.001φ*2.0±1.3 1.4±1.3 U=1205
p=0.031φ*
^ analyzed using Chi square test; φ analyzed using Mann Whitney U test; * statistically signifi cant
Table 5: Effect of variables on the number of correct answers on the anatomy test.
All participants (n=220) Participants watched video-demonstration (n=124)
Mean amount of correct answers
± SD Statistical analysis Mean amount of correct answers
± SD Statistical analysis
Intervention Continuous 2.1±1.2 U=4826
p=0.008φ*
2.4±1.0 U=1392
p=0.010φ*
Step-by-step 1.7±1.3 1.9±1.3
Age p=0.017^* p=0.111^
Gender Female 1.9±1.2 U=4732
p=0.535φ
2.2±1.1 U=1556
p=0.993φ
Male 1.8±1.5 2.2±1.3
Watched the video-demonstration Watched 2.2±1.2 U=3916
p<0.001φ*Not applicable
Not watched 1.5±1.4
Additional lesson high school
teacher
Yes 2.4±1.2 U=2857
p=0.004φ*
2.5±1.2 U=1227
p=0.058φ
No 1.8±1.3 2.1±1.1
Time high school teacher spend p=0.146^ p=0.549^
^analyzed using Chi square test; analyzed using Mann-Whitney U test; * statistically signifi cant.

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Citation: Nazari T, Zeb MH, Dankbaar MEW, Lange JF, van Merriënboer JJG, et al. (2019) Continuous versus step by step training for learning surgical anatomy on
an open inguinal hernia model. J Surg Surgical Res 5(2): 097-0102. DOI: https://dx.doi.org/10.17352/2455-2968.000082
to 1.5 correct answers in the students that did not watch the
video-demonstration, U=3916, p<0.001. Within the continuous
and step-by-step group, the students that watched the video-
demonstration scored signifi cantly higher on the anatomy
knowledge test than students that did not watch the video,
p<0.001 and p=0.031, respectively (Table 5). The gender and
age of the students that watched and did not watch the video-
demonstration were similar. In the continuous group, more
students watched the video-demonstration when the high
school teacher spent more time in class discussing the online
course (p=0.011). In the step-by-step group, more students
watched the video-demonstration when the high school
teacher gave additional lessons (p=0.002) and spent more time
in class (p=0.001).
Table 5 shows the subanalysis of the students that watched
the video-demonstration. Of the 124 participants (56.4%) that
watched the video-demonstration of the surgical procedure,
the students within the continuous group answered an average
of 2.4 questions correctly, and the students in the step-by-
step group answered 1.9 questions correctly, U=1392, p=0.010.
In this sub-selection, age (p=0.111) and additional lessons of
high school teachers (U=1227, p=0.058) were non-confounding
variables.
On the different statements of the cognitive load (internal
consistency of Cronbach’s alfa=0.707) and the total rating
of the cognitive load, no signifi cant differences were found
between the continuous and the step-by-step group (Table 1).
Discussion
In this study, the effects of a video-demonstration of a
surgical procedure based on the step-by-step framework
on anatomy knowledge and cognitive load were compared
to a continuous video-demonstration. High school students
studied a surgical procedure with an emphasis on anatomical
structures and were tested on their anatomical knowledge. The
continuous group answered slightly more questions correct
on the anatomy knowledge test compared to the step-by-step
group. The cognitive load was similar for the continuous group
and the step-by-step group.
The continuous group was on average older than the step
by step group, which was a confounding variable. In the sub-
selection of the students that watched the video-demonstration,
age was, however, no confounding variable. A more critical
factor for answering more correct answers was the preparation
by watching the demonstration video. Our results suggest that
the transfer of anatomical knowledge in pre-novices may be
better when information is presented continuously.
Based on previous studies, the expectation was that the step-
by-step group would score higher on the anatomy knowledge
test and lower on the cognitive load [12-14]. Moreno reported
that the segmentation group outperformed the continuous
group and had a lower cognitive load [14]. In both experiments
of Moreno, they included pre-service teachers (average age 25
years old) in an introductory educational psychology course in
their last semester of the teacher education program. Moreno
selected participants with knowledge in the fi eld they were
tested in, contrary to our students that did not know the open
inguinal hernia repair. Our participants were also younger
compared to Moreno’s participants. In a study with elementary
school students (age 9 to 11), studying the causes of day and
night, the segmented group outperformed the continuous
group [15].
Our high school students studied a surgical procedure
with its relevant anatomy, which might be more complex to
comprehend for high school students compared to the causes
of day and night. The students in both groups had a low
number of correct answers in the anatomy knowledge test,
indicating they might have been too novice and had too little
prior knowledge to be able to learn the open inguinal hernia
repair and its anatomy adequately. They were likely unfamiliar
with the medical jargon used in the video-demonstration and
textual description. Exposing students to information that
is too complex for their level of expertise, risks overloading
their cognitive abilities and impairs learning [5,16,17]. Further
research comparing step-by-step to continuous video-
demonstration should be performed in participants with
more medical knowledge, such as medical students, surgical
residents or surgeons.
The data suggested a similar experienced cognitive load in
both groups. This was, however, not measured immediately
after viewing the course, but during the test day. Furthermore,
the assessment included the entire online course and not the
video-demonstration exclusively, which could also explain the
same cognitive load in both groups [11].
We expected that some high school teachers would discuss
the online course in class. In the continuous and the step-by-
step group, the number and the duration of additional lessons
were similar. As high school teachers are no experts in open
inguinal hernia repair, they likely could only either stimulate
the students to do the online course or could watch the video-
demonstration in class. Within the sub-selection of students
that watched the video-demonstration, there were no effects
of the high school teacher’s additional lessons on the number
of correct answers on the anatomy knowledge test.
In the step-by-step group, we built-in a pause of 3 seconds
after each segment. All participants could pause and re-
watch the video-demonstration themselves. Indeed, in the
continuous group, this perhaps led learners to create their
own segmentation. We could not monitor how many times the
students paused or watched the video-demonstration. In case
the continuous group students watched or paused the video-
demonstration more times compared to the step-by-step
group, the segmentation effect of the step-by-step group may
have been diminished [12].
The cluster randomization occurred by school in order to
avoid students sharing access to the continuous and step-
by-step video-demonstrations. Unfortunately, this led to a
signifi cant difference in the age distribution between the groups.
In the complete selection, older age resulted in signifi cantly
more answers correct in the anatomy knowledge test. Within

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https://www.peertechz.com/journals/journal-of-surgery-and-surgical-research
Citation: Nazari T, Zeb MH, Dankbaar MEW, Lange JF, van Merriënboer JJG, et al. (2019) Continuous versus step by step training for learning surgical anatomy on
an open inguinal hernia model. J Surg Surgical Res 5(2): 097-0102. DOI: https://dx.doi.org/10.17352/2455-2968.000082
Copyright: © 2019 Nazari T, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use,
distribution, and reproduction in any medium, provided the original author and source are credited.
the selection that watched the video-demonstration, age did
not affect the mean correct answers of the anatomy knowledge
test. Before cluster randomization, the differences per high
school should have been assessed.
Conclusion
In summary, we found that the continuous group scored
slightly higher on the anatomy knowledge test compared to
the segmented step-by-step group. The subjects in this study
might have been too novice as both groups answered a low
number of anatomical questions correct. Further research on
online video-based course on inguinal hernia repair should test
more experienced learners to investigate the hypothesis that a
step-by-step framework facilitates learning by optimizing the
use of the cognitive capacity and subsequently, the learning
process.
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