ABSTRACT
Epidemiology is about observing whether certain things called ‘factor(s)’ (or ‘exposure(s)’) are connected (‘associated’) with certain problems (e.g. ‘health states’, ‘diseases’, ‘disabilities’), and if association exists, quantifying the relationship. Further, it provides a framework for assessing whether such associations are causal in nature. This chapter is about the evidence that specific and general housing factors cause disease, or more generally ill health, where ill health, unlike disease, is defined entirely by the self-reported symptoms of the people themselves.
