Logo of amjphAmerican Journal of Public Health Web SiteAmerican Public Health Association Web SiteSubmissionsSubscriptionsAbout Us
Am J Public Health. 1994 May; 84(5): 825–829.
PMCID: PMC1615050

The logic in ecological: I. The logic of analysis.


This paper addresses ecological studies in public health research in terms of the logic of their analysis. It makes several distinctions between studies based on ecological and individual units. First, it identifies the variables common to both types of study and those particular to ecological studies. Second, it shows how ecological and individual units combine in two classes: unmixed (purely ecological, purely individual) and mixed. Third, it details how the relationships among and between individual and grouped units (expressed in terms of regression coefficients between independent and dependent variables) yield four coefficients: for all individual members; for all groups; for all individuals within each group; and for all individuals within groups (a weighted average). Equipped with an understanding of the dimensions involved at ecological and individual levels and of the relationships between them, researchers are in a position to exploit the public health potential of the ecological approach.

Full text

Full text is available as a scanned copy of the original print version. Get a printable copy (PDF file) of the complete article (1.3M), or click on a page image below to browse page by page. Links to PubMed are also available for Selected References.

Selected References

These references are in PubMed. This may not be the complete list of references from this article.
  • Brenner H, Savitz DA, Jöckel KH, Greenland S. Effects of nondifferential exposure misclassification in ecologic studies. Am J Epidemiol. 1992 Jan 1;135(1):85–95. [PubMed]
  • Greenland S, Morgenstern H. Ecological bias, confounding, and effect modification. Int J Epidemiol. 1989 Mar;18(1):269–274. [PubMed]
  • Greenland S. Divergent biases in ecologic and individual-level studies. Stat Med. 1992 Jun 30;11(9):1209–1223. [PubMed]
  • Morgenstern H. Uses of ecologic analysis in epidemiologic research. Am J Public Health. 1982 Dec;72(12):1336–1344. [PMC free article] [PubMed]
  • Susser M. The logic in ecological: II. The logic of design. Am J Public Health. 1994 May;84(5):830–835. [PMC free article] [PubMed]
  • Halloran ME, Struchiner CJ. Study designs for dependent happenings. Epidemiology. 1991 Sep;2(5):331–338. [PubMed]
  • Koopman JS, Longini IM, Jr, Jacquez JA, Simon CP, Ostrow DG, Martin WR, Woodcock DM. Assessing risk factors for transmission of infection. Am J Epidemiol. 1991 Jun 15;133(12):1199–1209. [PubMed]
  • Koopman JS, Prevots DR, Vaca Marin MA, Gomez Dantes H, Zarate Aquino ML, Longini IM, Jr, Sepulveda Amor J. Determinants and predictors of dengue infection in Mexico. Am J Epidemiol. 1991 Jun 1;133(11):1168–1178. [PubMed]
  • Piantadosi S, Byar DP, Green SB. The ecological fallacy. Am J Epidemiol. 1988 May;127(5):893–904. [PubMed]
  • Frost CD, Law MR, Wald NJ. By how much does dietary salt reduction lower blood pressure? II--Analysis of observational data within populations. BMJ. 1991 Apr 6;302(6780):815–818. [PMC free article] [PubMed]
  • Rush D, Kristal AR. Methodologic studies during pregnancy: the reliability of the 24-hour dietary recall. Am J Clin Nutr. 1982 May;35(5 Suppl):1259–1268. [PubMed]

Articles from American Journal of Public Health are provided here courtesy of American Public Health Association


Related citations in PubMed

See reviews...See all...

Cited by other articles in PMC

See all...


  • Cited in Books
    Cited in Books
    PubMed Central articles cited in books
  • PubMed
    PubMed citations for these articles

Recent Activity

Your browsing activity is empty.

Activity recording is turned off.

Turn recording back on

See more...