Ethnic labels.

In epidemiologic studies of two binary exposure factors, much attention has been given to the concept of synergism of the factors. The leading dictionary of epidemiology offers two definitions of synergism, one of which this author labels statistical and the other biologic. The epidemiologic literature has been largely concerned with statistical synergism, which is typically measured using additive or multiplicative interaction. This paper focuses on biologic synergism, on the related concept of biologic parallelism, and on the question of how much information can be gleaned about population amounts of biologic synergism and parallelism--information which is of vital interest to epidemiologists. A fundamental identity equates the difference between the amounts of biologic synergism and parallelism to the additive interaction. Two biologic models, the multistage model and the no-hit or immunity model, enhance the interpretation of multiplicative interaction as a measure of statistical synergism, but it is pointed out here that, unfortunately, both models incorporate the strong assumption that there is no parallelism. A third model, the single-hit or vulnerability model, makes the even stronger assumption that there is no biologic synergism and consequently that the additive interaction is equal to minus the amount of parallelism. A consequence of this fact is that a link which has been perceived in the literature to exist between the single-hit model and the additive interaction is false.

Epidemiologic Methods↗

PubMed1997

[Prospective epidemiologic study for the determination of lung cancer risk groups (1975-19940].

Authors make known the comprehensive results of a longitudinal epidemiological examination which commenced in the 10th District of Budapest with nearly 100,000 inhabitants in 1975. The observation period is 15-20 years. Its aim was the determination of the risk factors of lung cancer. They followed up the lot of 30,561 persons, 92% of the population over 40 years of age 14,191 patients took part in a control examination supplemented with respiratory test. They analysed the connection between the supposed external risk factors and parenchyma functional damages caused by them and the development of lung cancer by detailed mathematical statistical arithmetic. 571 patients fell ill with lung cancer. The cured lung tuberculosis also proved to be a leading risk factor besides smoking. From the not endangered group 43, the highly super highly endangered groups 458 people fell ill with lung cancer. There was no difference between men and women in the lung cancer risk of the risk free population. According to their supposition the connection between the parenchyma functional damages caused by external risk factors and the development of lung cancer is determined by the different immunological status of people. (During the 20 years observation period 4% of heavy smokers and 3% of cured lung tuberculous patients fell ill with lung cancer). They urge the organization of wide ranging international prospective examination for the testing of this supposition.

Epidemiologic Methods↗