Essential Evidence-based Medicine, Second Edition (Essential ...

The medical literature: an overview 25
The New England Journal of Medicine and the Journal of the American Medical
Association (JAMA) are the most widely read and prestigious general medical
journals in the United States. The Lancet and the British Medical Journal (BMJ)
are the other top English-language journals in the world. However, even these
excellent journals print imperfect studies. As the consumer of this literature, you
are responsible for determining how to use the results of clinical research. You
will also have to translate the results of these research studies to your patients.
Many patients these days will read about medical studies in the lay press or hear
about them on television, and may even base their decisions about health care
upon what the magazine writers or journalists say. Your job as a physician is to
help your patient make a more informed medical decision rather than just taking
the media’s word for it. In order to do this, you will need to have a healthy skepticism
of the content of the medical literature as well as a working knowledge of
critical appraisal. Other physicians, journal reviewers, and even editors may not
be as well trained as you.
Non–peer-reviewed and minor journals may still have articles and studies that
give good information. Many of the articles in these journals tend to be expert
reviews or case reports. All studies have some degree of useful information, and
the aforementioned articles are useful for reviewing and relearning background
information. Bear in mind that no matter how prestigious the journal, no study
is perfect. But, all studies have some degree of useful information. A partial list
of common and important medical journals is included in the Bibliography.
What are the important types of articles?
Usually, when asked about articles in the medical literature, one thinks of clinical
research studies. These include such epidemiological studies as case–control,
cohort or cross-sectional studies, and randomized clinical trials. These are not
the only types of articles that are important for the reader of the medical literature.
There are several other broad types of articles with which you should be
familiar, and each has its own strengths and weaknesses. We will discuss studies
other than clinical research in this chapter, and will address the common types
of clinical research studies in Chapter 6.
Basic science research
Animal or basic science research studies are usually considered pure research.
They may be of questionable usefulness in your patients since people clearly are
not laboratory rats and in vitro does not always equal in vivo. Because of this,
they may not pass the “so what?” test. However, they are useful preliminary studies,
and they may justify human clinical studies. It is only through these types