Studies of disease occurrence

This chapter reviews the options for population selection in undertaking investigations aimed at estimating the occurrence of a disease. In terms of measuring disease occurrence, an important issue will be determining the appropriate target population. The choice will depend on being able to access the population, how representative it is, the size of the population, and the population data accuracy. It will not always be possible to use an ‘ideal’ population, there will be different options and the advantages and disadvantages of each will need to be determined. The same principles apply, however, if the object of the study is to investigate the occurrence of a risk factor, such as cigarette smoking, or other human attributes.