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Case control, cross sectional, and cohort studies

Types of epidemiological (observational) study designs

Belbasis L, Bellou V. Introduction to Epidemiological Studies. Methods Mol Biol. 2018;1793:1-6. doi: 10.1007/978-1-4939-7868-7_1. PMID: 29876887.

Ecological studies. In: Epidemiology for the uninitiated, 4th edition. Retrieved March 25, 2024 from: https://www.bmj.com/about-bmj/resources-readers/publications/epidemiology-uninitiated/6-ecological-studies

NOTE: A word of caution for the next set of filters: Authors do not always use the appropriate terminology when describing their epidemiologic studies. This is true for the above as well, but we have noticed that the following study types are more frequently not identified as such in their titles or citations. Not only that, but a retrospective study can be a type of cohort study or it can be a type of case-control study! Use these filters with some caution. They will locate the kinds of study they should, but only when the author knows what kind of study they have done and has described it as such!


Epidemiologic studies (Updated 23 August 2024)

"Epidemiologic Studies"/ or (epidemiologic* adj (studies or study)).ti,ab,kf,kw.

Note: This picks up the very broad term only. See below for specific types of epidemiologic studies.


Case-control studies (Updated 13 May 2024)

Case-Control Studies/ or Matched-Pair Analysis/ or (case adj2 control).ti,ab,kf,kw.


Cohort studies (Updated 13 May 2024)

cohort studies/ or longitudinal studies/ or follow-up studies/ or prospective studies/ or retrospective studies/ or (cohort or longitudinal or prospective).ti,ab,kf,kw.


Cross sectional studies (Updated 13 May 2024)

Cross-Sectional Studies/ or Prevalence/ or ((association adj2 (studies or study)) or (ecological adj (studies or study)) or cross-sectional or prevalence or prevalences or  transversal).ti,ab,kf,kw. or (association or associations).ti.


Case-crossover and case-time-control studies (Updated 13 May 2024)

These are epidemiological study designs that I am not familiar with but this article does describe when and how to use them:

  • Greenland S. Confounding and exposure trends in case-crossover and case-time-control designs. Epidemiology. 1996 May;7(3):231-9. doi: 10.1097/00001648-199605000-00003. PMID: 8728434. (Article link requires Pitt login)

((case adj crossover) or ((case adj time) and (time adj control))).ti,ab,kf,kw.

Incidence & Prevalence studies

Incidence studies (updated August 8, 2018)

Incidence/ or (incidence or incidences).ti,ab,kf,kw.


Prevalence studies (updated August 7, 2018) 

Prevalence/ or cross-sectional studies/ or (prevalence or prevalences).ti,ab,kf,kw.