For questions 1 through 6, please refer to the following information: Studies have shown that low vitamin D is associated with impaired fertility, endometriosis, and polycystic ovary syndrome. Vitamin D regulates the antimullerian hormone (AMH), follicle-stimulating hormone, mRNA, and expression of genes in reproductive tissues, implicating a role in female reproduction. Lata et al. conducted a prospective study to compare AMH levels in infertile and fertile females with vitamin D deficiency. Among the 35 fertile females (group 1), the mean AMH level was 3.47 with a standard deviation of 2.59. Among the 35 infertile females (group 2), the mean AMH level was 1.94 with a standard deviation of 1.30. Assuming the variances are unequal and a 0.05 significance level, use the confidence interval method to test the claim that infertile females have different AMH levels compared to fertile females. To do so, answer each of the following questions. 1. What is the null hypothesis (H0)? (1 point) a. 1 - u2 = 0 b. 1 - u2 0 c. 1 = u2 d. 1 - 2 =0 e. 1 = 2 f. Both a and c are correct g. Both d and e are correct

PubH 6002: Biostatistical Applications for Public Health 2. What is the alternative hypothesis? (1 point) a. 1 - u2 = 0 b. 1 - u2 0 c. 1 u2 d. 1 - 2 0 e. 1 2 f. Both b and c are correct g. Both d and e are correct 3. What is the critical value? (1 point) a. 1.691 b. 1.668 c. 1.995 d. 2.032 4. What is the standard error? (1 point) a. 0.11 b. 0.33 c. 0.49 d. 0.99 5. What is the 95% confidence interval? Provide an appropriate interpretation of this confidence interval. (1 point) a. There is a 95% chance that the true mean difference in AMI levels will fall within the interval (0.53, 2.53) when comparing fertile females to infertile females. b. There is a 95% chance that the true mean difference in AMI levels will fall within the interval (0.70, 2.35) when comparing fertile females to infertile females. c. We are 95% confident that the interval (0.53, 2.53) actually does contain the true mean difference in AMI levels when comparing fertile females to infertile females. d. We are 95% confidence that the interval (0.70, 2.35) actually does contain the true mean difference in AMI levels when comparing fertile females to infertile females. e. Both a and c are correct f. Both b and d are correct

PubH 6002: Biostatistical Applications for Public Health 6. What conclusion should you make regarding the null hypothesis? (2 points) a. Because the interval does not include 0, reject the H0 due to sufficient evidence and conclude that fertile females have a different mean AMI level compared to infertile females. b. Because the interval does not include 1, reject the H0 due to sufficient evidence and conclude that fertile females have a different mean AMI level compared to infertile females. c. Because the interval does not include 3.47, reject the H0 due to sufficient evidence and conclude that fertile females have a different mean AMI level compared to infertile females. d. Because the interval does not include 0, fail to reject the H0 due to insufficient evidence and conclude that fertile females do not have a different mean AMI level compared to infertile females. e. Because the interval does not include 1, fail to reject the H0 due to insufficient evidence and conclude that fertile females do not have a different mean AMI level compared to infertile females. f. Because the interval does not include 3.47, fail to reject the H0 due to insufficient evidence and conclude that fertile females do not have a different mean AMI level compared to infertile females. For Questions 7-13, refer to the following information: Alexander (2014) studied the necessary critical thinking skills for public health practitioners compared to how critical thinking skills were taught in MPH programs. Let us suppose that 7 students were randomly selected from a population of MPH students to participate in a program to enhance critical thinking to prepare them for the skills needed to be successful MPH practitioners. Each student was given a critical thinking task prior to training and was re-evaluated after the training. Higher scores on the task indicated more critical thinking skills used, such as identifying and assessing issues, analyzing data relevant to the issue at hand, and reflecting on the results in order to address the issues. Before and after training scores for critical thinking are below, resulting in a mean difference of -3.69 and an of 2.187. Assuming the results are normally distributed, test the claim that the program increased critical thinking skills using a 0.05 significance level. Participant 1 2 3 4 5 6 7 Before 3 2.1 4.3 5.2 5.5 6.0 2.7 After 7.4 6.5 8.1 10.0 9.1 5.0 8.5 7. What type of test should you use to test the null hypothesis? (1 point) a. Two sample t-test for variances assumed unequal b. Two-sample Z-test c. Paired t-test d. Two sample t-test for variances assumed equal

PubH 6002: Biostatistical Applications for Public Health 8. What is the null hypothesis? (1 point) a. 1 2 > 0 b. 1 2 c. 0 d. > 0 e. < 0 f. 0 9. What is the alternative hypothesis? (1 point) a. 1 2 > 0 b. 1 2 c. 0 d. < 0 e. > 0 f. 0 10. What is the critical value? (1 point) a. 1.645 b. 1.960 c. -1.943 d. -1.960 e. -1.645 11. What is the value of the test statistic? (1 point) a. -4.46 b. -4.30 c. 0.29 d. 9.08

PubH 6002: Biostatistical Applications for Public Health 12. What conclusion should you make regarding the null hypothesis? (1 point) a. Fail to reject the null hypothesis due to insufficient evidence and conclude that the critical thinking training did not increase critical thinking skills. b. Fail to reject the null hypothesis due to sufficient evidence and conclude that the critical thinking training did increase critical thinking skills. c. Reject the null hypothesis due to insufficient evidence and conclude that the critical thinking training did not increase critical thinking skills. d. Reject the null hypothesis due to sufficient evidence and conclude that the critical thinking training did increase critical thinking skills. 13. Two genetic variants, BRCA1 and BRCA2, are associated with increased risk of breast and ovarian cancer in women. According to the latest estimates by the National Cancer Institute, the incidence of breast cancer by age 70 is 0.635 among women with the BRCA1 variant. Among a group of 5 women identified as having the BRCA1 variant, what is the probability that exactly 2 women will be diagnosed with breast cancer? (2 points) a. 0.111 b. 0.138 c. 0.196 d. 0.400 For questions 14-17, refer to the following information: In one study of 63 women with the BRCA1 variant, 26 were diagnosed with breast cancer by age 70. Use a 0.01 significance level to test the claim that among women with the BRCA1 variant, that less than half (or less than 50%) are diagnosed with breast cancer by age 70. To test the hypothesis, you'll need to answer the following questions. 14. What is the null hypothesis (H0)? (1 point) a. = 0.50 b. < 0.50 c. 0.50 d. = 0.50 e. < 0.50 f. 0.50

PubH 6002: Biostatistical Applications for Public Health 15. What is the alternative hypothesis (H1)? (1 point) a. = 0.50 b. < 0.50 c. 0.50 d. = 0.50 e. < 0.50 f. 0.50 16. What is the value of the test statistic you should use to test the given hypothesis? (1 point) a. -2.175 b. -2.82 c. -1.38 d. 1.65 e. 0.12 17. If the p-value (corresponding to your test statistic) is 0.0838, what conclusion should you make? (2 points) a. Because p > 0.01, fail to reject the null hypothesis due to insufficient evidence and conclude that at least half of women with the BRCA1 variant are diagnosed with breast cancer by age 70. b. Because p > 0.05, fail to reject the null hypothesis due to insufficient evidence and conclude that at least half of women with the BRCA1 variant are diagnosed with breast cancer by age 70. c. Because p > 0.05, reject the null hypothesis due to sufficient evidence and conclude that less than half of women with the BRCA1 variant are diagnosed with breast cancer by age 70. d. Because p > 0.01, reject the null hypothesis due to sufficient evidence and conclude that less than half of women with the BRCA1 variant are diagnosed with breast cancer by age 70