[Methodological problems of evaluation of electrolyte intake in the clinical and population studies]

The paper deals with methodological problems of electrolyte intake in clinical and population-based studies. Marked inter- and intraindividual fluctuations were found to substantially affect the reliability of assessing the intake of electrolytes, which should be borne in mind in practice. Specifically, individual-based reliable characteristics of electrolyte intake (excretion) may be obtained after examining at least 8 daily urinary collections. The adequate validity of group electrolyte intake may be attained when a group consists of at least 8 persons. It is shown that it is feasible to employ the definite urine amounts to gain an insight into electrolyte intake.