- One important characteristic of analytical study is using comparison group for arriving a conclusion.
- When we give a comparison its validity increases. (Drug is used & some child died – report will be weak, if there is a comparable group & give us facts & figures)
- Political priority – Role of analytical study in establishing a political priority. To convince the policy maker you have to show as much as possible without the least amount of doubt that what you are saying is truth e.g. for stopping smoking lot of revenue will be lost. So you should go with full brief mechanism.
- To identify source, vehicle, vector or risk factor of infection for prevention & control purposes
- By establishing the association of a cause with a particular condition one can be taken effective measure with priority and can also be made aware about the magnitude of the problem.
- To establish legal reasons in addition to microbiological & enviromental evidence specially in case of drugs which may have serious adverse effects.
- Example: by analytical study the epidemiologist established association between cause and effect or exposure and effect. So if it can be established that certain condition/exposure causes certain disease, legal action can be taken to ban that particular condition or exposure. Since in case of cigarette smoking absolute cause for lung cancer or CHD could not be established, regarding it ban no legal action could not ban taken so far. But in case of paracetamol containing diethyl glycol it could be established beyond doubt that the glycol content was responsible for the mortality of children, so legal action was taken against those pharmaceuticals.
- Training & teaching purpose
- To inform public health authority or formulation of public health policy.