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Goal of this assignment:

• learn to use bibliographic sources to search for biomedical literature
• read technical research articles in endocrinology
• critically evaluate research articles
• determine whether claims for usefulness of advertised hormones are justified
• write a well-reasoned argument for or against the advertiser's claims

Assignment:
Choose one of the advertisements distributed in class, either for DHEA (the "DeAging Nutrient") or for ASD (used by Mark McGwire). These ads claim that there are "scientific studies" showing that use of these hormones is both safe and effective.

Search the scientific literature to find three articles that do or don't support the claims made in the ads. Read the articles, evaluate their significance, and write a paper to support or refute the advertiser's claims.

Literature search: 
Since the late 1800s, Index Medicus has published lists of the titles of all biomedical research articles in an indexed form.  This print version is available in the Engineering Library (1st floor Mudd) and in the Health Sciences Library uptown.   The National Library of Medicine has put this data base on-line, so you can search there instead.  The URL is http://www4.ncbi.nlm.nih.gov/PubMed/ . 

If you search here for the single word "DHEA", you'll get over 5000 entries, so try to limit your search by adding additional terms to your search, such as:  DHEA and fat.  Start also by limiting your search to the last five years, by changing the setting in the "Date limit" box;  if you don't find what you need there, you can remove the limit to include older articles.

Your search will produce a list of  titles of articles.  Click on the authors' names to see an abstract of the article, if available.   You are only required to read 3 articles, but I suggest that you find about 5-10 articles that sound interesting, and then skim through the articles to decide which you want to read thoroughly. The articles should be original research articles, not review articles. The Biology Library (6th floor Fairchild) and Psychology Library (Schermerhorn, campus level) will have some of the journals, but most journals in physiology will be found at the Health Sciences Library.  It's open on weekends and late at night, and can be reached by the campus shuttle bus (see bus schedule)or by taking the 1/9 train to 168th Street.

Critical evaluation:Being critical in this case doesn't mean that you label the authors a bunch of idiots. This definition from WWWebster Dictionary is more appropriate: " 'critical' may also imply an effort to see a thing clearly and truly in order to judge it fairly." Consider the possible weaknesses of the hypothesis, of the method of data collection and of data analysis, of the conclusions that are drawn. As we've discussed in class, rarely does a research experiment lead to an unassailable conclusion; the eventual design of any experiment is the result of compromises between what one theoretically would like to do and what is actually possible. Usually the authors of the study are themselves aware of the limitations of their experiments, and may "help" by inserting some critical comments in their Discussion.

Some questions you might ask in formulating a critique:

• Does the number of subjects studied seem sufficient to draw conclusions?
• What was actually measured? Would some other endpoint be expected to give different results? More accurate results? More relevant?
• Do the data provide sufficient evidence for the authors to answer the question they posed? What additional evidence seems necessary?
• Is the data consistent with more than one possible interpretation? What further experiment would need to be done to resolve this ambiguity?
• Is the information here sufficient evidence for the claims made by the advertisers? Are they telling the truth, the whole truth, and nothing but the truth?

Don't include details that are extraneous to your critique/summary. For example, a study of humans will provide details about the subjects, such as their age, occupation, weight, and so on. These details are included so that others can repeat the experiment exactly, and it's usually not necessary for you to mention them, although you should do so if this is the basis for your critique. For example, "This demonstration that H stimulates muscle growth is not convincing evidence that body-builders would benefit, because most body-builders are much younger than the 90 year olds studied here."

Intended audience.  Write for an audience of other students in this class, not for professional scientists.  To avoid writing in scientific jargon you should read the article, write some notes on what you want to say, and then put the article aside while you are writing. Write as if you were writing for the New York Times, not for the Journal of Incomprehensible Physiology. Look in a scientific/medical dictionary or in a textbook if there are important terms in the article that you don't understand. "Translate" the scientific prose into English to show that you understood what you read. For example, "After consensual diagnosis by at least three MH-CRC psychiatrists, all subjects were found to have no lifetime history of a mental disorder by DSM-III-R criteria" might be translated as "All the people were mentally healthy."

You can find additional suggestions for writing at Writing the Research Paper. The information there is for students writing papers describing their own research, but there are some good pointers on writing in general, and a list of useful books on writing.

Length:Your paper should be about 5 pages long. That means five pages of concise description, analysis and critique, not five pages of meandering all over the place till you make your point. Don't write something like

My paper is based on the article, "The Old Man and the C (response)", by Drs. X, Y and Z, who work at the University of Q and published this in 1997. They were interested in the effect of Hormone H on the cogno-intellectual response of elderly men. So they did an experiment. They injected H into 23 elderly men ranging in age from 75 to 85 and then they measured their cogno-intellectual response using the standard tests for IQ, PsiQ, PDQ, and Bach. They found that H doesn't have any effect on cogno-intellectual response.

Injections of H didn't affect cogno-intellectual response in elderly men (X, Y and Z, 1997).

Format for references:
When listing the references on which your paper is based, use the format
Author(s). Publication year. Article title. Journal title Volume: Page numbers
Stern, K., McClintock, MK.  (1998) Regulation of ovulation by human pheromones. Nature 392: 177-179.

Within the text of paper, you can refer to articles as follows:

Spelling counts.  Use a spell-checker or a dictionary.

Plagiarism:  Plagiarism is taken very seriously at Columbia University.  It can lead to academic disciplicinary action and possible dismissal from the University.  Plagiarism includes using the work of another person as if it's your own, as well as using the words of another author without attribution.