ABSTRACT
Geomedical investigators should make themselves familiar with the type and quality of all the main health data sources in their country. Medical registrations or health data have been restricted to observations of this type of variable and do not include observations of lower levels of human and animal biology. A feasibility evaluation consisting of a set of main questions and answers should always be a prior part of a geomedical investigation and starts with evaluation of the hypothesis on which the desire for an investigation is based. The frequency with which a nonfatal disease is mentioned on the death certificate gives an estimate of the prevalence of this disease in the deceased population. From a global perspective, cause-of-death diagnoses are most probably the easiest available disease data which fulfil certain basic quality requirements. Death certificates mentioning malignant disease, but not in accordance with or not found in the database are subject to further investigation.
