NSE 31A/B Lecture : CLASS 4 - Theory.doc
Document Summary
Epidemiology: defined as the study of the occurrence and distribution of health-related states/events in specified populations including the study of the determinants influencing such states & the application of this knowledge to control the health problem. It s purpose is to describe, explain, predict and control challenges to population health. Epidemiologists seek health-related events by answering questions who, what, where, when and by following trends in the population. They also examine causality & modes of transmission. Then, controls are established to prevent new illness, cure if possible and rehabilitate/prevent complications. Sub-disciplines can be divided into two-streams: the exposure-oriented sub-disciplines (e. g. nutritional, social, environmental, the disease-oriented sub-disciplines (e. g. cancer, injury, prenatal) Some sub-disciplines have less clear categorizations such as occupational, or molecular epidemiology. John graunt was the first to study statistics of epidemics and noted, for instance, gender differences in births (more males than females), seasonal variations in deaths, & high levels of infant deaths.