One reason why researchers rarely examine whether prevention programs reduce incidence rates is thatGroup of answer choicesthere are no tools for measuring outcome.it is necessary to have a very large sample to detect a difference.it is unnecessary to conduct this type of research as long as high-risk samples are targeted.all of the above.

What is the primary reason that relatively few studies have examined whether various prevention programs are effective in reducing incidence rates?Group of answer choicesInsufficient statistical power due to small sample sizes.Measurement issues.Sample representativeness issues.Accumulating samples from different studies has inadequate support as a methodology.

Which of the following statements are true regarding prospective studies?Group of answer choicesCan be used to estimate a relative riskCan be used to estimate an odds ratioConsiders random samples from each of the two outcome categories which are followed back (retrospectively) to determine the presence or absence of the risk factor for each individualConsiders subjects initially identified as disease-free and classified by presence or absence of a risk factorOften takes a long time to complete

True or False: Case-control studies can directly measure the risk or rate of a health outcome?TrueFalse

Cohort studies allow true determination of incidence of an outcome.Question 2Select one:TrueFalse

Which prevention activity is most effective with diseases that spread through direct contact?Group of answer choicesStandard precautionsQuarantinePharmaceuticalsEducation