Source of Information on Health should be from Respondent and Community not from Health Worker

Most important point in the validity of any research is the information about the problem should be taken from sample of the study (respondent) or study population not from health workers. There are many of academic and research centers classified the research data into two types of sources are active and passive resources. According to this basis, the researches that be established basis on passive resource will be incompletely valid and can't depend on it in scientific research ether cant generalize these results because these researches have built according to resources effected by more than one type of bias.