“While it may be dramatic to demonstrate our technical skill in replacing blocked arteries, or even replacing the human heart with a mechanical device, risk factor reduction is a far more realistic, cost-effective and humane approach to resolving this serious health issue.”
Unless proper attention is given to epidemiological studies, there will be little prospect of reducing the incidence of major diseases such as childhood diabetes, epilepsy and Alzheimers, and medicine will be restricted to the often painful and costly control of symptoms with powerful drugs and surgery.
Nevertheless, population studies do have their limitations. Critics argue that epidemiologists cannot always carry out experimental trials with volunteers and are “limited” to observing what has already occurred, whereas laboratory scientists can manipulate animals in any way they see fit: after all, animals are regarded as disposable. In addition, when poorly designed population studies produce conflicting results, scientists may feel justified in turning to animal experiments. But as Professor Matanoski of the Johns Hopkins University explains,47
“Resolution of conflicting data will not be achieved by abandoning human data, but rather by examining more thoroughly the available information on humans to identify and eliminate the flaws in the existing (study) designs and methodologies so that eventually risk estimates can be based on data from the true reference population, the human.”
Whatever its limitations, the overwhelming advantage of epidemiology is its direct relevance to human disease. Not only that but observations can be made on hundreds of thousands of people whereas experiments on similar numbers of animals would be prohibitively expensive. No practicable animal experiment, for instance, could have proved that small doses of X-rays to a foetus in its mother’s womb, would result in one cancer in every 2000 individuals during childhood, as was shown by epidemiological studies in Britain and the United States in 1958 and 1962.23
|<<Previous||Back to Study of Disease||Next>>|