Social and economic instability induced a drastic increase in the incidence of diseases involving temporary disability among the oilmen of West Siberia in recent years. Multifactorial analysis disclosed the principal risk factors causing the formation of groups of subjects falling ill frequently and for a long time. The structure of risk factors in the multifactorial model of incidence of diseases with temporary disability has changed recently, reflecting the situation in Russia. The sanological approach to studies of morbidity helps effectively develop a system of complex measures aimed at primary prevention, which should be adapted to the local conditions. One approach is the creation of screening tests to be used in prophylactic check-ups, based on estimation of the threshold (critical) number of risk factors.