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Rxexam's Biostatistics Questions & Answers www.pharmacyexam.com © All Rights Reserved RxExam’s Biostatistics Questions & Answers 2019-2020 Edition MANAN SHROFF 1 www.pharmacyexam.com © All Rights Reserved This book is not intended as a substitute for the advice of physicians. Students or readers must consult their physician about any existing problem. Do not use information in this book for any kind of self-treatment. Do not administer any dose of mentioned drugs in this book without consulting your physician. The author is not responsible for any kind of misinterpreted, incorrect, or misleading information or any typographical errors in this book. Any doubtful or questionable answers should be checked in other available reference sources. All rights reserved. No part of this book may be reproduced or transmitted in any form or by any means, electronically Photocopying, recording, or otherwise, without prior written permission of the publisher. RXEXAM® is a registered trademark of Pharmacy Exam of Krishna Publications Inc. Any unauthorized use of this trade mark will be considered a violation of law. 2 www.pharmacyexam.com © All Rights Reserved 1. In biostatistics, confounding is normally defined 5. The scores of Naplex for 10 students are 75, 82, as: 90, 92, 67, 95, 110, 80, 82, 86. Find the mean for the above data. a. One chosen from a carefully defined population with the aid of a formal method to avoid bias. a. 83.6 b. 85.9 b. A formal method to assign subjects by chance to c. 836 one or the other treatment. d. 43 c. The effect of two or more variables that do not 6. The scores of Naplex for 10 students are 75, 82, allow a conclusion about either one separately. 90, 92, 67, 95, 110, 80, 82, 86. Find the median for the above data. d. The systematic tendency of any factors associated with the design, conduct, analysis, and a. 110 evaluation of the results of a trial to make the b. 84 estimate of a treatment effect deviate from its true c. 82 value. d. 67 2. The data that categories patients as males or 7. The scores of Naplex for 10 students are 75, 82, females are known as: 90, 92, 67, 95, 110, 80, 82, 86. Find the mode for the above data. a. Random data b. Nominal data a. 75 c. Ordinal data b. 90 d. Interval data c. 86 d. 82 3. Which of the following data represents interval continuous data? 8. Classifying continuing educational experience into categories including “strongly agree,”“agree,” a. A number of cigarettes smoked per day by a and “disagree,” is an example of which type of person. variable or data? b. A number of children in a household. c. Height of children. a. Nominal d. Number of languages a person speaks. b. Ordinal c. Interval 4. Data can be transformed by using the logarithm, d. Ratio square root, or reciprocal. Which of the following is the most common data transformation used in 9. Which of the following statements about the medical research? prevalence is/are TRUE? a. data converted to log I. It is a measure of the rate of occurrence of a b. data converted to root condition. c. data converted to reciprocal d. data converted to ratio II. It is the number of new cases of a condition that develop during a specific period of time. III. It is the proportion of a population found to have a condition at a single point in time. 3 www.pharmacyexam.com © All Rights Reserved a. I only c. the risk of heart failure in patients taking the b. III only study drug was more than the risk of heart failure in c. II and III only patients taking placebo. d. All 14. What is the value of relative risk reduction if an 10. “One out of every 50 adults in the United States RR is 0.33? has depression.” This statement is an example of: a. 1.56 a. Incidence b. 0.33 b. Prevalence c. 0.67 d. 1.33 11. Which of the following statements best describe the relative risk (RR)? 15. What would be the absolute risk reduction if the incidence of heart attack was 2% in the intervention a. It is the risk of an event or outcome occurring in a group and 7% in the control group? group of interest in relation to a control group. a. 15% b. It usually states how much the treatment b. 5% reduced the risk of an outcome relative to the c. 2% control group. d. 7% c. It represents the absolute difference of the event 16. If the calculated absolute risk reduction (ARR) rate between the treatment and control groups. for heart attack event was 5.1%, what would be the number needed to treat? d. It is a representation of the number of patients who need to be treated to prevent one additional a. 11 event compared to treating the same number of b. 2.65 patients with the control therapy. c. 3.2 d. 20 12. Calculate the value of RR if the risk of heart failure associated with an invention drug is 5% 17. Which of the following statements is TRUE versus 9% with placebo? ABOUT the standard deviation (SD)? a. 1.25 a. It is used to calculate confidence intervals. b. 2.65 c. 0.55 b. It is used to determine variability of a sample d. 1.8 around a sample mean. 13. Which of the following statements best describe c. It is used to display bimodal or skewed data. the interpretation of value of RR obtained in a previous question? d. A large SD shows that individual data points are clustered closer to the mean. a. there was no association between the study drug and heart failure. 18. If the sample size in a study is 100 subjects and the SD for blood glucose is 10 mg/dl, what is the b. the risk of heart failure in patients taking the standard error of the mean? study drug was less than the risk of heart failure in patients taking placebo. a. 65.9 4 www.pharmacyexam.com © All Rights Reserved d. the regression model explained 30% of the total b. Employees who exposed to asbestos for more variance is not a good fit. than 10 years had 16% decreased odds of developing asthma than those who did not. 146. In a study examining the relationship between the drinking a coffee in the late evening and the c. The results are not significant because the likelihood of insomnia, the r2 value for the confidence interval includes 1.0. regression line is 1.0. What does this indicate? d. The results are not significant because the a. For each additional cup of coffee, chances of confidence interval is greater than 1.0. occuring insomnia increase by 1.0%. 149. What does “OR 0.4 95%CI 0.4-0.6 p <0.05” b. Since r2 equals 1.0, this indicates there is no mean? relationship between drinking coffee and developing insomnia. a. The odds of death in the intervention groups are 60% less than the odds of death in the control c. Since r2 equals 1.0, the regression line perfectly groups with the true population effect between fits the data. 60% and 40%. This result was statistically significant. d. For each additional cup of coffee, there is no effect on sleep. b. The odds of death in the intervention groups are 60% more than the odds of death in the control 147. Which of the following information is/are TRUE groups with the true population effect between ABOUT an odds ratio (OR)? 60% and 40%. This result was statistically significant. I. If the OR = 1 indicates there is no difference between the two arms of the study. c. The odds of death in the intervention groups are 60% less than the odds of death in the control II. If the OR is > 1 the control is better than the groups with the true population effect between intervention. 40% and 60%. This result was statistically NOT significant. III. If the OR is < 1 the intervention is better than the control. d. The odds of death in the intervention groups are 60% more than the odds of death in the control a. I only groups with the true population effect between b. I and II only 40% and 60%. This result was statistically NOT c. II and III only significant. d. All 150. A drug company-funded double blind 148. Suppose a study examined the relationship randomised controlled trial evaluated the efficacy between workers exposed to an asbestos for more of an adenosine receptor antagonist Cangrelor vs than 10 years and the risk of developing asthma. If Clopidogrel in patients undergoing urgent or the study found an increased risk of asthma in the elective Percutaneous Coronary Intervention (PCI) group who exposed to asbestos (OR: 1.16, 95% CI: who were followed up for specific complications for 0.9-1.5). What does this mean? 48 hrs (Bhatt et al. 2009). The results section reported “OR 0.65 95% confidence interval [CI], a. Employees who exposed to asbestos for more 0.55 to 0.83; P=0.005” What does this mean? than 10 years were 1.16 times less likely to develop asthma than those who did not. 21 www.pharmacyexam.com © All Rights Reserved a. The odds of death, myocardial infarction, ischemia-driven revascularization, or stent thrombosis at 48 hours after randomization in the Cangrelor arm were 35% less than in the Clopidogrel arm with the true population effect between 34% and 7%.
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