The vast scope of modern medicine has forced a high degree of specialization and the need for health professionals to concentrate almost exclusively in a narrow area of medicine. In the trial of a contested issue the possible scope of issues and admissible evidence is unlimited. An injured plaintiff may have injuries spanning multiple medical specialties such as internal medicine, surgery, psychiatry and osteology, and a PhD or an MD degree may have no bearing on a health professional's knowledge and expertise in any one of these specialties.

Trial attorneys also need information about aspects of medicine that medicine normally does not consider. For example a trial attorney would like to know:

	1)		About proximate cause, a different concept than the medical term etiology (meaning the causes of the disease);
	2)		The standard of care in the industry (a concept that often excludes the research findings relied on by health professionals);
	3)		Compensable damages (a different concept than injuries);
	4)		Whether there is any medical authority that would support contrary conclusions (a subject that is generally ignored by health professionals); and,
	5)		Whether there were pre-existing conditions and/or other factors that might mitigate damages, what they are, and the medical basis for claiming that they do.