Abstract This investigation was performed within the framework of the multicenter observational study «Epidemiology of Cardiovascular Diseases in the Regions of the Russian Federation». The second study (ESSE-RF2) was conducted to survey a random, stratified, multistage sample from the unorganized male and female populations of Omsk and the Omsk Region. The study response rate was 84%; 1659 people aged 25—64 years were examined; of them males were 45%. In the city, the maximum response rate was in the population aged 25—34 years (93%), also in the female population aged 55—64 years and in the rural one aged 45—54 years (91%). The female population was 10% more active in the examination than the male one. However, after starting the examination, the men completed it more often than the women. The organizational aspects that made it possible to get a high response rate were analyzed. These included the choice of a research base that was much closer to the place of residence of an invited contingent; the differentiation of responsibilities between local physicians and nurses on the one hand and a mobile team of scientists and senior students to perform laboratory and instrumental studies on the other; the involvement of the health facility (HF) administration (study participants) to the working process; the adjustment of the time of a sample survey during evenings, weekends, and holidays according to the requirements of the research process; and the regular monitoring of the bias/reliability of a sample within each HF, such as a participant, a subsample, and a whole sample.