The task of educating medical students in the critical appraisal skills required for properly evaluating clinical studies is a large one.
This web site has resource
material that may be useful in helping medical students recognize poorly
formulated statistics or inappropriately drawn conclusions in medical studies.
This web site has resource material that may be useful in helping medical students recognize poorly formulated statistics or inappropriately drawn conclusions in medical studies.
A number of medical studies with significant problems in either clinical trial design, medical statistics, or properly formulated conclusions are examined in detail. There will be differing viewpoints from those on this website regarding these case studies, but it is hoped those differences will provide useful starting points for discussion.
This web site besides being a collection of suboptimally performed or interpreted medical studies, also reviews some of the strengths and weaknesses of meta-analyses and large randomized clinical trials.
The information on this web site which has
been created by the author can be
used for the instruction of medical students and residents without restriction as long as the source is documented.
is hoped that this site will prove a useful resource.
The following is a summary of the content of this web site in regards to usefulness for educators of medical students:
Example 1: This is probably not particularly useful for medical
students. This has to do with a randomized clinical trial with an inherently
biased protocol. It does provide an example where a suboptimal treatment
protocol used in a clinical trial is a crucial factor in regards to the
implications of that trial for clinical practice.
Example 3: This study is an example of a trial's conclusions being the opposite of what the trial data suggests. This study would be useful for discussion. A potential for a type 2 statistical error is also illustrated as well. An example of a study in the New England Journal of Medicine where the conclusions run exactly the opposite of what the data suggests.
Example 8: This consists of comments by Dr. Peter Sleight in an insightful article regarding the hazards of inappropriate subgroup analysis. The Hazards of Subgroup Analysis (Are Gemini's really different?)
Example 9: The unfortunate saga of possible fraud in a medical study with a medical journal and a medical school failing to respond appropriately. The Columbia University 'Miracle' Study-
10: These topics may be useful as starting points for discussion
with medical students.
Example 11 How medical science advances when there are problems in the scientific literature. (How these particular issues might look "10 years later") This discussion of the self correcting aspects of the medical literature may be of interest.
Celebrex This may be useful as a
starting point for discussion with medical students regarding a multitude of
topics. One issue, is that of the reliability of cross trial comparison (particularly given that
drug representatives often will try to make invalid cross-trial comparisons). This is an example of comparing the placebo group from one
trial to a treatment group in another trial, which is always problematic.
The study was written by superb investigators, but this one aspect of the statistical
analysis is quite questionable. (On the other hand, this 2001 article in
JAMA brought beneficial widespread attention to the potential of a COX-2
inhibitor being associated with increased cardiovascular risk.)
The task of educators of medical students in the field
of interpreting clinical trials is a crucial one. Following
graduation, the students as physicians will be confronted with a barrage of
clinical trials. Skills helping to
discern optimally performed and interpreted clinical trials from those that are
inherently weak will be useful to the current student throughout his or her
career in medicine.
Example of bias apparent in a meta-analysis in 30 seconds:
A Type II Statistical Error Incorrect conclusions resulting
from insufficient numbers. Death
of the oat bran fad
Miscounted and Misinterpreted. How not to conduct a
5. The ALLHAT hypertension trial-- a detailed critique
Celebrex-- an unreliable
cross trial comparison
A Tale of Two Trials- A superbly conducted trial contrasted to a
suboptimally interpreted trial:
Limitations of Meta-analysis: overview:
Lessons from an unusual saga of possible fraud in the literature