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leagues. Even if they do not engage in research themselves, physicians
must know how to interpret the results of research and apply them to
their patients. Thus, a basic familiarity with research methods is essen-
tial for competent medical practice. The best way to gain this familiar-
ity is to take part in a research project, as a medical student or follow-
ing qualification.
The most common method of research for practicing physicians is
the clinical trial. Before a new drug can be approved by government-
mandated regulatory authorities, it must undergo extensive testing for
safety and efficacy. The process begins with laboratory studies fol-
lowed by testing on animals. If this proves promising, the four steps,
or phases, of clinical research, are next:
1
Phase one research, usually conducted on a relatively small num-
ber of healthy volunteers, who are often paid for their participa-
tion, is intended to determine what dosage of the drug is required
to produce a response in the human body, how the body processes
the drug, and whether the drug produces toxic or harmful effects.
2
Phase two research is conducted on a group of patients who have
the disease that the drug is intended to treat. Its goals are to de-
termine whether the drug has any beneficial effect on the disease
and has any harmful side effects.
3
Phase three research is the clinical trial, in which the drug is ad-
ministered to a large number of patients and compared to another
drug, if there is one for the condition in question, and/or to a pla-
cebo. Where possible, such trials are ‘double-blinded’, i.e., nei-
ther research subjects nor their physicians know who is receiving
which drug or placebo.
4
Phase four research takes place after the drug is licensed and mar-
keted. For the first few years, a new drug is monitored for side ef-
fects that did not show up in the earlier phases. Additionally, the
pharmaceutical company is usually interested in how well the
drug is being received by physicians who prescribe it and patients
who take it.
The rapid increase in recent years in the number of ongoing trials
has required finding and enrolling ever-larger numbers of patients to
meet the requirements of the trials. Those in charge of the trials,
whether independent physicians or pharmaceutical companies, now