The quantitative methods may make a precise description about the quantitative variables agreeing with the available information. Thus is possible to measure the relation between several variables too. The effective policies for the smoking control must make a precise estimation from the smoking economic impact especially from the smoking economic burden. That’s why several fiscal policies for the smoking control make an intensive use from the quantitative research methods to explain the smoking impact. In all described cases it is necessary to understand wholly the own essence and behavior of the researched variable. Thus will be possible identify the most practice method to obtain the main objective. These research methods have limitation respect to the qualitative methods. However, understand these limitations may make a trustable research agreeing with the researched variable. An example of this is the smoking control.