Epidemiology 2 EXAM QUESTIONS AND CORRECT DETAILED ANSWERS WITH RATIONALES (VERIFIED ANSWERS) ALREADY GRADED A+ NEWEST VERSION

Epidemiology 2 EXAM QUESTIONS AND CORRECT DETAILED ANSWERS WITH RATIONALES (VERIFIED ANSWERS) ALREADY GRADED A+ NEWEST VERSION The nature of the data affects the types of statistical analyses and inferences that are possible. - Answer- True The epidemiologic and clinical descriptions of a disease can be different - Answer- True Rates are not, but proportions and percentages are ratios - Answer- False, they are all ratios This calculation is similar to an incidence rate but typically for a shorter time period (e.g. time of an outbreak investigation) a. Incidence density b. Attack rate c. Secondary attack rate to incidence d. Prevalence - Answer- B. Attack rate When the duration of a disease becomes short and the incidence is high, the prevalence becomes similar to incidence - Answer- True For a chronic disease of high incidence and long duration, prevalence of the disease increases relative to incidence - Answer- False The incidence rate of a disease is defined as the number of new cases of the disease over a time period divided by the total population (at risk) during the same time period times a multiplier (e.g. 100,000) - Answer- True If your population of 230,109 had 502 deaths in a year, what is the crude mortality rate? - Answer- (502/230,109) x 100,000 = 218.2/100,000 If your expected number of deaths (based on a standard population) was 988, what is your Standardized Mortality Ratio? - Answer- 502/988 x 100 = 51% how is this interpreted? Mortality in your population is lower than expected when compared to the standard population. Controlled assignment -- experimental study -- non randomized assignment (quasi-experimental) - Answer- community trials Controlled assignment -- experimental study -- randomized assignment - Answer- clinical trials Uncontrolled assignment (non randomized) -- observational studies -- sampling w/regard to disease or effect - Answer- cross sectional and/or retrospective studies Uncontrolled assignment (non randomized) -- observational studies -- time span studies/ sampling with regard to exposure, characteristic, or cause - Answer- prospective studies Uncontrolled assignment (non randomized) -- observational studies -- sampling w/regard to disease or effect -- exposure or characteristic at time of study - Answer- cross sectional studies ecologic studies Uncontrolled assignment (non randomized) -- observational studies -- sampling w/regard to disease or effect -- history of exposure or characteristic (prior to time of study) - Answer- retrospective studies ecologic study - Answer- - unit of analysis is a group - use to generate hypotheses and also in analytic studies - descriptive and analytic - single point of data obds - directionailty of exposure usually unknown - use existing data (mortality rates) - correlation, chi squared - quick/easy/inexpensive cross sectional study - Answer- - descriptive - single point of obvs - collect exposure and disease histories at the same time - unknown if disease or exposure comes first - data from sample surveys - may use secondary data (school records, national surveys) - unit of analysis = individual - measure used = prevalence estimates - can be copleted w/in a short persiod of time/inexpensive