On ecological studies: a short communication.

The typical objective of research is to try and identify cause-and-effect relationships. As with any research design, there are strengths and weaknesses involved in trying to achieve this objective. Some study designs are stronger than others in attempting to establish cause-and-effect associations. The task of establishing cause-and-effect relationships is challenging (Hill, 1965) and any study that does not include experimentation, that is by manipulating a variable's exposure, is inhibited from drawing causal inferences (Heath, 1995). Similarly, statistical significance is also based on probability rather than certainty. This article focuses on a particular research design, namely, the ecological study, and attempts to serve as a reminder that the design has its place in the realm of various research designs.