A set of training materials for professionals working in intervention epidemiology, public health microbiology and infection control and hospital hygiene.
OJE published "Case-control studies: basic concepts"
Abs: The purpose of this article is to present in elementary mathematical and statistical terms a simple way to quickly and effectively teach and understand case-control studies, as they are commonly done in dynamic populations-without using the rare disease assumption. Our focus is on case-control studies of disease incidence (‘incident case-control studies'); we will not consider the situation of case-control studies of prevalent disease, which are published much less frequently.
Ref: Jan P Vandenbroucke and Neil Pearce: Case-control studies: basic concepts Int. J. Epidemiol. (2012) 41(5): 1480-1489 doi:10.1093/ije/dys147 http://ije.oxfordjournals.org/content/41/5/1480.full.pdf+html
Good reading !
The need to use case control in prevalent diseases occurs often. In that case we need to understand that 'the rare disease assumption' does not really exist, yet we need to think carefully about where we select our controls. The core principle is that we select controls because we want to measure 'how the exposure of interest is distributed in the population that gave rise to the cases.
On this topic, a very readable article appeared in Eurosurveillance. Olivier le Polain de Waroux and his co-authors do a great job describing and explaining the principles of case-cohort, with very useful examples.
I can invite everyone to read this piece:
Le Polain de Waroux O, Maguire H, Moren A. The case-cohort design in outbreak investigations. Euro Surveill. 2012;17(25):pii=20202. Available online: http://www.eurosurveillance.org/ViewArticle.aspx?ArticleId=20202