Teleoanalysis can be defined as the synthesis of different categories of evidence to obtain a quantitative general summary of (a) the relation between a cause of a disease and the risk of the disease and (b) the extent to which the disease can be prevented. Teleoanalysis is different from meta-analysis because it relies on combining data from different classes of evidence rather than one type of study.
Randomised trials with disease end points are often not enough to determine dose-response relations; their results tend to be limited by factors such as dose, duration of treatment, and a limited age range of subjects. We also need data from observational epidemiological studies (particularly large cohort studies) and often knowledge of the mechanism of action. Short term trials using drugs or vitamins are also helpful because a drug can have a large specific effect that is not otherwise achievable.
It may also be necessary to quantify the individual effects that relate to separate steps in a causal pathway—that is, the effect of factor A on disease C is determined from the estimate of the effect of A on an intermediate factor B and the estimate of the effect of B on C, rather than by directly measuring the effect of A on C. The exercise is like putting together the pieces in a jigsaw puzzle.
The adverse effects of interventions always need to be considered, and including them in the analysis will give an assessment of the benefit to harm ratio. However, inclusion of adverse effects relies more on monitoring than on interpretive analysis, and we will not consider it further in this article.
In contrast to meta-analysis, which increases the precision of summary estimates of an effect within a category of study, teleoanalysis combines different categories of study to quantify the relation between a causative factor and the risk of disease. This is helpful in determining medical practice and public health policy. Put simply, meta-analysis is the analysis of many studies that have already been done; teleoanalysis provides the answer to questions that would be obtained from studies that have not been done and often, for ethical and financial reasons, could never be done.