In medical practice and research it is necessary to consider the rights of the researcher or physician and of the subject or patient, to conform to scientific standards and to examine the appropriateness with respect to laws and moral values. Research ethics committees have an important role to play in ensuring the ethical standards and scientific merit of research on human subjects. Research of no scientific value is also against ethical principles. To obtain valid and reliable results from biomedical research, it is a scientific and ethical obligation to make use of the science of statistics. Therefore, for research to be evaluated using biostatistics intensively from ethical and scientific points of view, a biostatistics expert is necessary on research ethics committees. Developments in Turkey are used as examples.