Virtually every medical treatment
available to modern humans, from
drugs to devices to surgical
procedures to diagnostic
technology, stems from a
single source: Research
Better known as clinical
trials, clinical research seeks
to expand medical
knowledge through the study
of human volunteers (called
Clinical trials help to take the guesswork out of health care. To
illustrate why this is important, you need only consider how
“bloodletting,” or the practice of letting the
“bad blood” out of patients, was a common
medical treatment into the
Doctors also once used brutal
and ineffective treatments such
as trepanation (boring holes in
the skull) and mercury-
Controlled clinical trials, by finding out answers to specific medical
care questions, eliminate much of the ignorance and wishful
thinking that defined pre-20th century medicine.
Pre-20th Century Medicine
Indeed, clinical trials were one
of the primary drivers of
skyrocketing human lifespans
in the 20th century, and they
remain a key component of
knowledge of medicine.
Your participation in a clinical trial can help to nudge medical
knowledge ahead even further. In fact, there are many benefits to
taking part in clinical research. There are some risks, too. But
before delving into these pros and cons, a bit of background
information is in order.
The world’s first clinical trial
was performed by a military
leader, not a doctor, and
published in a religious text
rather than a scientific one.
First Clinical Trial
The Bible records the story of how King Nebuchadnezzar, ruler of the
Babylonians, ordered his people to eat only meat and drink only wine
in order to keep up their strength. Several young men of royal blood
objected to the king’s directive, preferring a vegetarian diet.
Nebuchadnezzar allowed these men to consume only legumes and
water for 10 days.
At the end of the experiment the king judged that the vegetarians
appeared better nourished than the meat-eaters, so he let them
continue with their dietary habits.
however, lacked many of the
characteristics of modern
Trustworthy Trial ?
For starters, the experiment was
subject to selection bias, as it was
not undertaken with a random
sample of all vegetarian Babylonians.
Only royal young vegetarians were
part of the experimental group,
which made it impossible to control
for variables such as gender and
socioeconomic status. There was no
way for the king to know whether
diet or something else (perhaps the
relative privilege of the young men)
accounted for the seemingly-better
health of the legume eaters.
Nowadays, clinical studies have much more rigorous
inclusion criteria. Inclusion criteria describe characteristics that
qualify prospective study subjects.
They include things like
gender, age, the type of
disease being treated,
and other known medical
conditions. For example,
the inclusion criteria for a
study of high blood pressure
would be a diagnosis of high
blood pressure. Studies
also have exclusion criteria.
Another shortcoming of the meat eater
vs. legume eater experiment was
that there was no reliable measure
of health among the participants.
While the young vegetarians
may have “appeared” to be
conclusion was based on
nothing other than the
Modern clinical studies measure outcomes more rigorously with
what’s known as endpoints. While some endpoints (including
quality of life) are subjective, most are objective (i.e. “tumor
shrinkage,” “progression free survival,” “disease free survival,” etc.).
Statistical evidence, based on a predetermined algorithm, lends
further weight to study outcomes.
National Breast Cancer Coalition,
The Hastings Center
Yet another issue with Nebuchadnezzar’s experiment was the lack
of a proper control group. A control group serves as a baseline
measure compared to the experimental group. It allows
researchers to eliminate and isolate variables in order to more
accurately measure study results.
Technically, Nebuchadnezzar did have a control group
(the meat eaters). The king, however, was not merely comparing
meat-eaters with legume-eaters (the experimental group), because
the former group drank wine and the latter drank water. If he’d
designed an experiment where one group
consumed water and meat and the
other water and legumes, the
results would have been
Nowadays, control group participants might receive a placebo
(an inactive product that participants believe is the test product,
but which doesn’t have any treatment value),
or an active treatment (one that has already been shown to work).
Placebo controls determine whether a treatment works, while
active controls determine how the experimental treatment
compares to the existing treatment.
A final—and arguably the most critical—problem with the early
Babylonian study is the lack of randomization. Randomization
means that participants as well as investigators do not choose
which participants are in the experimental group and which are in
the control group. Instead, they’re assigned by chance to one or
the other. Randomization is done to avoid bias.
Sources: The Hastings Institute, Hannan
Avoid Biased Resulted
If Nebuchadnezzar had truly abided
by modern clinical research
standards, his trial also would have
been single-blind or double-blind.
In a single-blind study, the patients
are not told what they’re being
given, but members of the research
team do know. In a double-blind
study, neither the patients nor the
researchers know what is being
administered; only the pharmacist
knows. As with randomized studies,
blind studies seek to eliminate bias.
Despite its flaws, the Old Testament
dietary study demonstrated how
human experiment could impact
Roughly 2,000 years would pass before
Randomized controlled trials (RCTs),
widely considered to be the “gold
standard” of clinical testing, came into
The Gold Standard
The first published RCTs appeared in the
late 1940s. The results of these
trials improved treatment of two
major killers at the time:
tuberculosis and malaria.
These landmark studies
ushered in a new era
Source: Archives of Disease
New Era of Medicine
Today, a clinical trial is defined as a multiphase study conducted by
researchers on human subjects to
test a medical treatment or
prevention strategy. The
medical treatment being
studied could be a drug,
a medical device, a surgical
procedure, or a therapy.
The goal of a clinical
trial is to determine
if a new intervention
works and is safe.
Sources: Collier, NIH
Safety and Efficacy
Clinical trials are conducted in phases, each with a different
purpose, number of patients, and length of study.
• Phase 1 trials test a drug/treatment in a small group (~20 to 100) of
patients in order to evaluate safety and identify side effects.
• Phase 2 trials may include up to several hundred volunteers and last
for several months to 2 years. Safety is further evaluated and
effectiveness is measured.
• Phase 3 trials last up to 4 years and recruit up to 3,000 volunteers.
During this stage of experiment, the experimental drug/treatment may
be compared with standard treatments, and more information on
safety and efficacy are gathered.
• Stage 4 trials are post-marketing studies done after a
drug/treatment/device has obtained FDA approval. They seek further
information about risks, benefits, and optimal use.
Sources: NIH, FDA
Well before human volunteers are recruited for any stage of
clinical trials, basic, pre-clinical research begins in laboratories.
Both cell studies and animal testing precede human testing.
Source: Columbia University Medical Center
Following laboratory work, the most promising experimental
treatments are moved into clinical trials. The study sponsor,
however, which could be a physician, a foundation, a federal
agency, a pharmaceutical company, or another group or
individual, must come up with a study protocol (a detailed
plan of the study) that is reviewed, approved and monitored
by an Institutional Review Board (IRB).
Sources: ClinicalTrials.gov, NIH
IRBs consist of physicians, researchers, and members of the
community who ensure that clinical trials are ethical and that
participants’ rights are protected. IRBs are federally regulated.
Sources: ClinicalTrials.gov, FDA
While the IRB may periodically review the research, day-to-day
clinical testing activities are overseen by a principal investigator
(PI), who is typically a doctor, and a research team consisting of
doctors, nurses, and other health care professionals.
Sources: ClinicalTrials.gov, NIH
Participants are also protected by the process of informed
consent. An informed consent document explains how the study
works as well as its risks and benefits. But even after a
participant signs the document, they’re free to withdraw from
the study at any time. The informed consent document is
reviewed by an IRB.
Hopefully it’s clear to you at this point
that clinical trial participants are not
“guinea pigs” or lab rats to be done
with as experimenters please. There
are numerous safeguards in place to
protect study patients, who are free to
opt out of trials whenever they want.
There are, of course, risks
involved with taking part in a
clinical study. Then again, any
medical test, drug, or
procedure has risks. The
specific risks of a given study
are outlined in the informed
consent document, and you’ll
be given ample opportunity to
ask questions about the study
before providing your consent.
Source: American Cancer Society
The National Institutes of Health (NIH) recommends that prospective
clinical trial participants consider two important risk factors:
• The degree of harm that might result
• The overall chance of harm occurring
The most common risk is that of minor discomfort. Less frequently,
complications require medical attention. Patients do—albeit very
rarely—suffer significant, even fatal, complications.
Factor The Risks
Aside from physical side effects,
be prepared to sacrifice some
portion of your free time as a
volunteer. You’ll not only have
to report to the study location
(such as a hospital, university,
doctor’s office, or community
clinic) on a regular basis, but
the study may continue for a
year or several years.
And some studies might require you to take actions (like wearing a
portable blood pressure monitor or other diagnostic/monitoring
equipment) away from the study location. In some cases, hospital
stays are required. There may be out-of-pocket expenses for test
drugs or treatments.
Source: Mayfield Clinic
To avoid unanticipated inconveniences, be sure to carefully read
the informed consent document and ask the researchers how the
study might affect your daily life.
As for the benefits of
participating in a clinical
trial, it depends
somewhat on whether
you are a healthy
volunteer or a patient
volunteer. Both types of
volunteers play a vital role
in medical research.
You Play a Vital Role
A patient volunteer is somebody
with a specific health problem or
who is at high risk to develop a
certain health problem. Patient
volunteers typically participate in
clinical research to better
understand, diagnose, treat, or cure
Source: Mayo Clinic, NIH
A healthy volunteer is somebody without a
significant health problem who participates
in clinical research. These volunteers help
researchers to define the limits of
“normal.” They are given the same test,
procedure, or drug as the patient group
and serve as controls for patient groups.
For patient volunteers, especially
those with cancer or other potentially
fatal conditions, participating in a
clinical trial could provide access to
new drugs or procedures that are
more effective than existing ones.
There is no guarantee, though, that
the drugs or procedures will benefit
Source: Harvard Medical School
Access to New Treatments
But even if your participation in a clinical trial doesn’t benefit
you directly, it could benefit others. Healthy and patient
volunteers alike can be proud that they are continuing the
human tradition of better living through research that began
with Nebuchadnezzar circa 500 BC and continues to this day.
From life-threatening diseases like AIDS, cancer, and diabetes to
annoying ailments like the common cold and hair loss to everyday
concerns like wounds, cavities, and skin aging, clinical trials are in
the works that may some day
provide major medical
ClinicalTrials.gov lists approximately 170,000 studies taking
place in all 50 states and in nearly 200 countries. To find one
near you, perform a search. Once you find a study you’re
interested in, ask your doctor for more information about the
drug or therapy being studied.
Where To Find Studies
As you search for a clinical trial near you, keep in mind that
each study has inclusion/exclusion criteria, and that participants
must qualify for a study. You’ll find out whether you qualify
after you schedule a pretrial screening. During the screening
you’ll get a chance to speak with the investigators and ask
Source: Mayo Clinic
Where To Find Studies
To learn more about clinical trials, check out the following
• The American Cancer Society
• U.S. Food and Drug Administration
• Mayo Clinic