When Can the Result of Epidemiologic Research Not Eliminate the Need To Invoke the Precautionary Principle?

Benefits and risks of ultrasound in pregnancy

Ultrasound is, arguably, the most commonly used diagnostic procedure in obstetrics. It is convenient, painless, yields immediate, extensive results, and is widely considered to be safe. Some (but not all) benefits described in the literature have been validated by evidence-based analysis, such as pregnancy dating. Others are considered clinically useful, although objective evidence may be less strong. As is the case with almost any medical procedure, however, its performance carries some risks: misdiagnosis on the one hand and possible undesired effects on the other. The general belief exists that diagnostic ultrasound (DUS) does not pose any risk to the pregnant patient nor to her fetus. Nonetheless, ultrasound is a form of energy and, as such, demonstrates effects in biological tissues it traverses (bioeffects). The physical mechanisms responsible for these effects are thermal or non-thermal (mechanical). It is the role of science to show whether any of these bioeffects may be harmful. A risk-benefit analysis may also be important, as well as education of the end users to assure patients' safety.

Understanding measurement of dental diseases and research participation in practice set-up

A general understanding of the measurement of dental diseases can help practitioners in the process of assessing the patient's future risk of disease. More importantly, as clinical studies shift from the traditional academic setting to practice-based networks, practitioners might play a more significant role in research. An important issue in oral health disease management in the future will be the standardization of clinical criteria and the development of alternative mechanisms of data collection for epidemiologic purposes.