[Use of the major components methods in epidemiological studies].

When multifactorial processes are analyzed, it is most rational to use the methods of multidimensional statistical analysis, including the major components methods. This method is rather new in epidemiological surveys. Its advantage is that it may be used to get information that is difficult derived by other ways.

[Informative value of the major component technique in the assessment of the epidemic tuberculosis situation].

The paper describes a method for comprehensive analysis of the epidemic situation which is based on the major component technique. The algorithm proposed for comprehensive assessment is highly effective in the retrospective analysis and in the analysis of the current material which includes a great deal of various characteristics that are at first sight occasionally unrelated. The use of the algorithm is shown by the example of analyzing 19 statistical variables that characterize the epidemic situation and different aspects of the work of a tuberculosis-controlling facility in 30 districts of the Novosibirsk Region in a period of 15 years (1985-1999).

[Dynamics of major constituents of tuberculosis morbidity in the population of Novosibirsk region].

After processing the dynamic series of tuberculosis morbidity in the population of the Novosibirsk region by the smooth component methods, two major constituents were defined in morbidity dynamics. In total, they make up about half the total variability of tuberculosis morbidity. The first constituent is due to socioeconomic causes that are common for the whole region.

[Factor analysis of rat behavior in the open-field test].

Method of major components, a variety of factor analysis, was used for evaluation of rats behaviour motivational structure in the open field test. 40 outbred rats of Wistar line (20 males and females) were examined in which 22 behaviour characteristics were studied. It was shown that a greater part (60%) of rats individual behaviour variability in the open field test was determined by the action of three major components (factors), which were defined as "investigation", "fear" and "shifted activity".