Observational Studies in Environmental Epidemiology

Epidemiology is the study of the distribution and determinants of disease in human population. To determine if a new drug is beneficial for treating a disease, a randomized controlled trial, which is an interventional study, is the gold standard of epidemiologic design. In environmental epidemiology, however, “observational” studies are the main source of epidemiologic data, i.e., people are exposed through the course of their lives rather than through an experiment.

Your textbook provides examples of observational studies addressing environmental health topics. Today, epidemiologic studies are commonly published in journals devoted to environmental health as well as in medical, public health, and other types of journals.

Articles from major journals are indexed by the National Library of Medicine in a database known as Medline, which you can search by typing the word “PubMed” into your search engine.

The PubMed site permits you to find journal articles addressing specific topics. If you are not familiar with searching PubMed, you can refer to the tutorials present on the PubMed site. You can also ask South University Online Library support staff to assist you.

For this assignment:

• Do a PubMed search with one of these epidemiologic search terms that represent observational study methods—”cohort” or “case-control.”
• Link the epidemiologic term you chose using AND with the environmental health term—pollution.
• Further specify your search with a term for the overall source of pollution such as air, water, waste, workplace, occupational, industry, mining, etc.
  • An example search strategy is—cohort [TI] AND pollution AND air.
  • Another example search strategy is—(case-control [TI] OR “case control” [TI]) AND pollution AND water.
  • The articles you retrieve may have a great deal of technical information about statistics and may present a seemingly overwhelming amount of data in the results section. For this assignment, concentrate on the study abstract, found in PubMed, and the portion of the methods section, which describes how the people who were evaluated were selected for study in the full-text version of the article.
• Prepare a 2- to 3-page report in a Microsoft Word document addressing the following points:
  • Retrieve the full text of an article using the above search strategy that addresses human health (not wildlife or ecosystems). Choose an original research study, not a review article that is an example of a cohort or case-control observational epidemiologic study concerning environmental health.
  • List the PubMed identifier (PMID) number from PubMed at the beginning of your paper so that the instructor can easily retrieve the article and review it (for example, PMID: 14769642).
  • Describe the study that you located with your PubMed search, including the number of people studied, where they were located, and the pollutant. This information will probably be in the title and abstract of the study.
  • Describe the main study question or hypothesis addressed by the study. For example, “Is well-water arsenic exposure higher among people with bladder cancer compared to people without bladder cancer?”
  • List how the studied individuals were selected. In most cases, this will be succinctly described in the methods section of the article.
  • Summarize the findings as noted in the study’s abstract.
  • Describe the importance of the study’s findings to human health.
  • Provide a title page that includes the title of this assignment, your name, the section of the course in which you are enrolled, and the date.
  • Include the full bibliographic citation of the article chosen and other appropriate references.