Choosing a study sample is an important step in any
research project since it is rarely practical, efficient or
ethical to study whole populations. The aim of all quan-
titative sampling approaches is to draw a representative
sample from the population, so that the results of
studying the sample can then be generalized back to
the population. The selection of an appropriate method
depends upon the aim of the study. Sometimes less
rigorous methods may be acceptable, such as incidental
or quota samples, but these methods do not guarantee