Efficacy of Visual Diagnostics
on General Surgery Shelf
Examination Performance
Anthony Charles MD MPH FACS
Department if Surgery
Method




The 2007-2008 UNC SOM class are the historical controls
The 2008-2009 UNC SOM class are the visual diagnostic study cohort
There are six groups in each year
The Study group is exposed to the visual diagnostic pretest at beginning of
the surgery clerkship. Test results are communicated to each student.
 The test comprises of 40 surgical pictures pertinent to the surgical
curriculum, in which a surgical diagnosis can be made based on the image
and attention to overt clinical cues.
 Posttest and discussion of test answers and Shelf exam review is
performed at the end of the eight week clerkship
 IRB was granted and consent was obtained from each participating medical
student
Results
Table 1.
Variable
Obs
Mean
Std.
Dev
Shelf Control
154
74
80
103
73.03
51.6
67.7
79.6
7.8
9.9
10.7
8.8
Pretest
Post test
Post test Shelf
Score
Fig.1.
This Box
20
40
60
80
100
plot illustrates the statistically significant improvement from pre test top post
test. P<0.0001
Pretest
possttest
Fig. 2. This Box plot illustrates the statistically significant improvement in the
shelf score of the study group exposed to the visual diagnostic study compared
to the historical controls.
100
90
80
70
60
50
cohortcontrolshelf
Conclusion
Vis Dx
Exposure to the visual diagnostic study
shows a statistically significant
improvement on Shelf Scores.