Principles of Epidemiology & Epidemiological methods “I keep six honest serving men, they taught me all I know their names are what, why when, how where & who” Introduction: Preventive & Social Medicine è Epidemiology As siej are basic sciences. Epidemiology of gall to do choronic diseisellently works well. Epeedemic oti investigation dicit the place of origin of Epidemłology. Recent Hi Epidemiology oil is highly developed. Epidemiology method is used