In general, the study of an occupationally exposed population has a threefold aim: - to ascertain which effects are associated with the exposure; to set up methods and means for the prevention of the effects; to verify the efficiency of the control measures taken. What makes such an approach "comprehensive"? A comprehensive study should ideally take into account all the factors involved in the exposure-response relationship under study. These factors relate mainly to the definition of exposure and effect and to the selection of the index and referent population. Unlike the experimental setting, the real world of a factory makes it difficult to clearly meet many of the criteria which characterize a valid and comprehensive study. Some of these difficulties are covered and discussed with reference to the specific area of neurobehavioral "risks". First, which type of study is better suited when we are dealing with multiple exposures and different outcomes? The time aspects of the exposure - outcome relationship must be carefully considered to design a proper study. In defining the exposure, different sources and methods are available: their relative merits and drawbacks are briefly discussed. The population of interest is very seldom the one currently at work: many selection factors are working, too. The choice of a control group raises problems, especially if the control subjects are not active workers. The validity of the measurement instruments employed should also be stated. Many additional factors are of interest when studying an exposure-response relationship: they may act as confounders or as modifiers of the effect, and the difference should be appreciated. A comprehensive study ought not to be primarily "significant", but "meaningful". On the other hand a causal inference cannot only rest on statistics, but the nature and the characteristics of the exposure - outcome association should be thoroughly examined.
|Number of pages||11|
|Journal||Advances in the Biosciences|
|Publication status||Published - 1983|
- effect modification
- Epidemiologic methods
- occupational exposure
- study design