Using observational information in planning and implementation of field studies with children as subjects

Children have been one of the least-studied populations for estimating environmental exposure, even though they are cited as a sensitive subgroup for diseases derived from environmental exposure. This trend appears to be changing as more studies are conducted with children as subjects. It consequently becomes increasingly important to gather and use observational data in all phases of the study. Observational data are the key for both defining the pathway of exposure and for assessing effectiveness of the data-collection protocols. Obtaining quality data from a study involving children requires: efficient use of observational data, collection of meaningful personal and microenvironmental samples, linkage of observational data to the collected samples, and personnel trained to work with children using pilot-tested protocols. Although all of these help to ensure the quality of the data, the utility of the data is often determined by observational feedback from those who collected it. Laboratory-derived protocols should be living documents and observations from the field should be used to modify the data-collection methods when practical.