The socially significant behavior model was extended with hidden variables for more accurate assessment of the intensity. These hidden variables are characterizing the actual respondents' last episodes values, cause due to the social significance of behavior respondents' answers can be shifted. The purpose of the paper is to analyze this extended model. The functioning of the extended model is considered and compared to the original model. Examples of its using are shown. Obtained results can be used in different research fields, e.g. sociology and epidemiology.