Abstract:
:Case-control studies are usually defined to investigate risk factors for a single disease of interest. However, subsequent to data collection, investigators may wish to examine as an 'outcome' a variable that was an exposure in the original study. A naive analysis that disregards the sampling strategy that gave rise to the data is clearly prone to bias. We present here a simple approach to the analysis of such data using an appropriately weighted regression model. Viewing the problem as a two-stage design provides a unified framework for recognizing and defining the necessary weights when confronted with a variety of real data problems that at first seem unrelated. We provide illustrations that highlight the generality of the approach and demonstrate that the method gives essentially the same results as more specialized methods that require non-standard tools for analysis.
journal_name
Stat Medjournal_title
Statistics in medicineauthors
Reilly M,Torrång A,Klint Adoi
10.1002/sim.2398subject
Has Abstractpub_date
2005-12-30 00:00:00pages
4009-19issue
24eissn
0277-6715issn
1097-0258journal_volume
24pub_type
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