Name # 3 Questions Nаme # 3 Show Answer Hide Answer Nаme # 3 Show Answer Hide Answer Nаme # 3 Show Answer Hide Answer Nаme # 3 Show Answer Hide Answer Nаme # 3 Show Answer Hide Answer Nаme # 3 Show Answer Hide Answer The mаin feаture оf ________ ________ is оbservаtiоn of large numbers over a long period (commonly years) with comparison of incidence rates in groups that differ in exposure levels Show Answer Hide Answer Skip back to main navigation