Abstract
Traditionally, statistics has been viewed as the branch of science which
deals with association. Many epidemiological research questions, however,
are concerned with causation, not association. In this thesis we develop
novel statistical methodology to address four epidemiological problems
properly, from a causal inference point of view. We show, that for these
four problems, our methods offer an attractive alternative to the
`standard' methodology, which may not yield the desired (causal)
inference.
