Epidemiological analysis

The committee recommends that investigators, including CDC, that conduct surveys of biomarkers in the population should routinely collect detailed information about SES, lifestyle, and other cofactors on each subject and routinely present results organized so as to address the question of whether biomarker concentrations vary as a function of each. Epidemiologic analyses of biomarkers in relation to health should routinely include appropriate adjustments for such covariates. 

The combination of the health-relevant time-window and the toxicokinetic properties of the agent of interest determine the optimal exposure assessment strategy. Dioxin, a contaminant of chlorophenoxy herbicides and fungicides, has a relatively long biological half-life, estimated at about seven years and is measurable in serum. Serum measurements of dioxin are therefore relatively stable, and simple first-order kinetics have been used to back-estimate serum dioxin levels on the basis of an occupational history. Such exposure data have been used quite successfully in epidemiological analyses of cohorts of pesticide producers (Hooiveld et al, 1998). 

Three-dimensional dose-rate/time/response surfaces for chronic exposure to carcinogens and ionizing radiation clarify the interactive roles of competing risks (Raabe, 1987). The three dimensions are average dose rate, exposure time, and risk. The unproved conceptualization afforded by them contributes to the planning and evaluation of epidemiological analyses and experimental studies involving chronic exposure to radiation toxicants (Raabe, 1987). 

Duhme H, Weiland SK, Keil U Epidemiological analyses of the relationship between environmental pollution and asthma. Toxicol Lett 1998 102-103 307-316. 

Therapeutic agents are a frequent and underestimated cause of adverse immune-mediated reactions (Bachot Roujeau, 2001 Demoly Bousquet, 2001). Although a few epidemiological analyses have been published, they are often confounded by the absence of a clear-cut diagnosis. Clinical outcomes can be the result of immunoallergic, pseudoallergic, or autoimmune-like mechanisms. 

Ursin, G., Ziegler, R. G., Subar, A. F., Graubard, B. I., Haile, R. W., and Hoover, R., 1993, Dietary patterns associated with a low-fat diet in the National Health Examination Follow-up Study Identification of potential confounders for epidemiologic analyses, Am. J. Epidemiol. 137 916-927. 

The main uses of accident and incident data such as the techniques for learning from the analysis of aggregated accident and incident data, using trend analysis, comparisons of accident and incident data, and epidemiological analyses. 

It is this type of informahon which is best used for the sorts of analyses discussed earlier since it is common to all incidents and can, tiierefore, be used for trend, comparison and epidemiological analyses. 

There are two types of accident and incident data to be considered, the aggregated data used for trend and epidemiological analyses and the data on single accidents and incidents collected during investigahons. Each of these data t) es is dealt with separately. 

Various study methodologies, including statistical and epidemiological analyses, studies of safety attitudes and safety behavior, case studies, nearaccident studies, motion and work experiments, interviews and others, have been conducted over... 

A recent development involves the use of software that automatically codes narrative or free-text data (Stout in Feyer and Williamson, 1998). This type of software has the potential to make coding more reliable and consistent, but is best suited for epidemiological analyses of large databases, e.g. on a nation-wide basis. 

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