Epidemiology, methods

Naturalistic population-based studies use epidemiological methods to attempt to identify outcomes from real world clinical practice in large, heterogeneous populations. 

Hu H, Aro A, Rotnitzky A. 1995. Bone lead measured by x-ray fluorescence Epidemiologic methods. Environ Health Perspect 103(Suppl 1) 105-110. 

The difference between establishing that two events are associated, in a statistical sense, and the difficult task of establishing that one event causes the other, will be discussed more fully in Chapter 6 Identifying carcinogens, as will many other features of the epidemiology method. 

Most scientists would hold that these unknowns and uncertainties in the regulatory risk-assessment model would tend to favor risk overestimation rather than underestimation or accurate prediction. While this view seems correct, it must be admitted that there is no epidemiological method available to test the hypothesis of an extra lifetime cancer risk of about 10 per 1000 000 from methylene chloride in drinking water. The same conclusion holds for most environmental carcinogens. It is also the case that more uncertainties attend the risk assessment process than we have indicated above. 

The assignment of the patient to a par- (h) ticular therapeutic strategy is not decided in advance by a trial protocol but falls within current practice and the prescription of the medicine is clearly separated from the decision to include the patient in the study. No additional diagnostic or monitoring procedures shall be applied to (i) the patients and epidemiological methods shall be used for the analysis of collected data ... 

Pharmacoepidemiology is traditionally defined as the discipline concerned with the study of the use and effects of drugs in large numbers of people. It applies epidemiologic methods, knowledge, and reasoning to the subject of clinical pharmacology and... 

H.T. Dean, The investigation of physiological effects by the epidemiological method, in F.R. Moulton (Ed.), Fluorine and Dental Health, American Association for the Advancement of Science, Washington, DC, 1942, pp. 23-31. 

Axelson (1985) Epidemiologic methods in the study of spontaneous abortions Sources of data, methods, and sources of error. In Hemminki K, Sorsa M, Vainio H ed. Occupational hazards and reproduction. Washington, DC, Hemisphere, pp 231-236. 

Lemasters GK (1993) Epidemiology methods to assess occupational exposures and pregnancy outcomes. Semin Perinatal, 17(1) 18-27. 

The following section discusses the three main steps of the biomarker validation process, or the fife cycle of a biomarker (1) its identification and development, (2) its validation using epidemiological methods, and (3) its application in etiological or clinical studies. 

It is important to note that not all human studies that can be used to evaluate effects meet the scientific rigor of the epidemiological method, the characteristic that differentiates an epidemiological study from others conducted in humans. The essential elements include the following ... 

A brief discussion of each feature can be found later in this chapter. Underlying the epidemiological method are two assumptions first, that disease does not occur randomly and, second, that systematic study can identify factors that cause or can prevent disease (Hennekens and Buring 1987). Those design features help to ensure the scientific validity of human data, and they underscore the added strength and utility of epidemiological data that contribute to assessment of human health risk from toxicological hazards. 

All epidemiological studies should be critically evaluated with respect to research design (especially in relation to study purposes), methods, analysis, and interpretation of results. Evaluation requires all aspects of the epidemiological method to be weighed carefully, as shown in Box 2-2. 

Evaluating human studies requires careful assessment of all elements of the epidemiological method. This is not an easy process, and it requires understanding of research methodology and appreciation of biostatistics. 

Scientifically sound epidemiological studies adhere to the essential elements of the epidemiological method ... 

Gail, M. H. NCI, NIH Consulting on epidemiologic methods Division of Cancer Etiology... 

Kahn, H. A. (1983). "An Introduction to Epidemiological Methods." Oxford Univ. Press, New York. 

Lihenfeld AM, Pedersen E, Dowd JE. Cancer Epidemiology Methods of Study. Baltimore, MD Johns Hopkins Press, 1967 72. 

Cannabis in the New World Committee Reports on Marijuana Epidemiology Methods of Use Active Ingredients Pharmacokinetics Absorption... 

The general application of epidemiologic methods to developmental toxicity is described below and followed by a discussion of laboratory studies in rodents and rabbits. The bulk of data available in developmental toxicology are based on these protocols. Since the difference in human and animal response appears to rest in large part on differences in behavior, physiologic parameters, and xenobiotic absorption, distribution, metabolic fate, and elimination, a brief description of transplacental pharmacokinetics is also provided. 

Klingberg MA and Weatherall JAC (eds.) (1979) Epidemiologic methods for detection of teratogens. Contributions to Epidemiology and Biostatistics. Basel Karger. 

---