True/False 1. True or False? To calculate the finalized n for a study, one should take the total number of participants needed to ensure the desired confidence interval and divide it by the proportion of individuals expected to be retained throughout the course of the study.

2. True or False? A researcher wants to be sure the mean difference in the change in blood pressure has a margin of error no more than 5 points and the difference in the standard deviation between the mean blood pressure points from the first medication used to treat high blood pressure and the second medication used to treat high blood pressure is 14 points. The desired sample size required to ensure a 95% confidence interval for the proposed study used to compare the efficacy of two medications used to treat high blood pressure during a cross-over trial is n = 31.

3. True or False? A researcher wants to estimate the impact prenatal care during pregnancy can have on premature deliveries by conducting a retrospective case-control study on new moms. If the prevalence of premature births is approximately 10.9%, the researcher should enroll a total of 586 women in the study if the researcher wants to construct a 90% confidence interval for the difference in proportions that has a margin of error of no more than 3%.

4. True or False? It is not important for researchers to account for attrition or loss of participants during follow-up.

5. True or False? The effect size is the difference in the parameter of interest that represents a clinically meaningful difference (in standard deviation units).