QUESTION 27 0.5 pc At the beginning of a clinical trial, two treatment groups are compared for baseline differences in depression rating. Both groups include 10 participants each. Group 1 had an average depression score of 17.5 (SD = 3.2), and Group 2 had an average score of 19.2 (SD = 2.8). What is the 2tailed p-value of the appropriate comparison of means? 0 -2.195 O -0.27 O 0.4 O 0.04 QUESTION 28 0.5 pc Agroup of patients with schizophrenia and their twin siblings without schizophrenia are in a genetic study. Their neurological scores are compared. The scores of the patients with schizophrenia are 81, 88, 81, 55, 90, and 89. The scores of their twin siblings without schizophrenia were 55, 75, 64, 78, 67, and 66. What is the 2tailed pvalue for the appropriate ttest comparison? 0 0.1389 0 0.024 O 0.02 O 0.08 QUESTION 25 0.5 pc Entrance exam scores from 10 randomly selected students from Queens are compared with those of 1 O unmatched students randomly selected from Brooklyn. The scores are: Brooklyn: 87, 83, 99, 75, 81, 89, 87, 86, 80, 88, and Queens: 90, 89, 81, 67, 92, 94, 70, 85, 84, 77. What is the t-value of the ttest of group means? O -0.81 O 0.44 O 0.47 O -0.73 QUESTION 26 0.5 pc An examination of leg strength comparing 5 men and 5 women in an exercise class showed than the men had a higher scale mean (45.6) than the women (43.2). Assuming a common SD of 5.5, what is the t-value of the appropriate test comparing means? O 1.6 O 0.98 O 0.38 O 0.14 QUESTION 27 0.5 pc QUESTION 23 0.5 pc Two groups are randomized to receive a vaccine intranasally or intravenously. The antibody scale mean of the intranasal group is 188.2, SD = 8.0, n = 20 and that of the intravenous group is 177.2, SD = 3.5, n = 20. What is the tvalue of the ttest of group means (assuming equal variance)? O 11 O 5.75 O 0.00 O 14.5 QUESTION 24 0.5 pc Evaluation scores from a group of 7 individuals are compared before and after a training on personal health. The data are (before/after): 11/15, 10/12, 13/09, 14/14, 15/16, 09/15, and 12/15. What is the 2tailed pvalue for the ttest of the difference between before and after scores? O 0.05 O 0.21 O 0.01 O 0.12 QUESTION 21 0.5 p According to population data, the mean hematocrit volume in red blood cells is 18.3 nl. The mean in a random sample data of 50 participants is 19.5 nl, with an SD of 3.4. What is the 2-tailed p-value for the appropriate statistical test comparing the sample mean with the population mean? O 0.0126 O 0.0159 O 2.5 O 0.05 QUESTION 22 0.5 p What is the margin of error for a 95% confidence interval based on the data values: 42.9, 40, 41.1, 42 and 48.8? O 1.54 O 42.96 O 4.27 O 2.8 QUESTION 23 0.5 p