Studies in standardization : serum cholesterol analysis performed for epidemiological investigations

Cardiovascular diseases are the major cause of death in industrialized countries. Death rates from coronary heart disease have increased steadily up to some 30% of the total death toll - they have stabilized in the past ten years and even seem to decline. The relative youth of the victims remains particularly disturbing (2 - 6). The etiology and pathogenesis of the disease are stili incompletely known (7). From a considerable number of epidemiological studies, however, a great many risk indicators (or risk factors) have emerged (8 - 13). The most hnportant among these are elevated blood pressure, elevated serum cholesterol levels and cigarette smoking. The design and objectives of large scale trials have, as a rule, been quite variable. It has been recognized that the conductance of such studies -the recruitment of a representative target population, the data handling, etc. -is an extremely complicated task. Comparability of the several fmdings is limited (14) and in view of the need to exchange useful scientific information the various study methods must be standardized (15, 16, 17). This need also applies to the measurement of cholesteroL Comparability requires also the compatible analysis and presentation of results and sufficient description of all procedures. In many countries official and unofficial recommendations