Fundamentals of Biostatistics
8th Edition
ISBN: 9781305268920
Author: Bernard Rosner
Publisher: Cengage Learning
expand_more
expand_more
format_list_bulleted
Question
Chapter 8, Problem 175P
To determine
Identify the test used to compare the means of two groups.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionStudents have asked these similar questions
Coronary stenosis (narrowing of the artery supply to the heart muscle) is a direct cause of heart disease. A theory suggests that chronic cytomegalovirus (CMV) infection narrows coronary vessels and leads to coronary heart disease. To test this theory, 75 patients undergoing angioplasty were followed for 6 months following their procedure. The 49 patients who were seropositive for CMV experienced an average luminal diameter reduction of 1.24mm (s1 = 0.83 mm). In contrast, the 26 patients who were seronegative for CMV experienced and average luminal reduction of 0.68 (s2 = 0.69).k Test whether this mean difference in luminal reduction is significant. Show all hypothesis-testing steps. Do the data support the hypothesis that chronic CMV virus infection plays a role in coronary luminal reduction? What is the 95% confidence interval?
Transepidermal water loss (TEWL) is a measure of the rate that water crosses the skin
through diffusion and evaporation. In general, damaged skin has a higher TEWL than
nondamaged skin. A report submitted to the U.S. Food and Drug Administration
(Therapeutic Equivalence of Topical Products, A. Bunge, B. N'Dri-Stempfer, et
al., 2007) described an experiment in which the outer layer of skin on a small area of the
foream was partially removed in order to measure the concentration of a certain drug.
TEWL (in g/m? per hour) was measured both before and after skin removal. The results for
10 individuals were as follows.
Subject
Before
After
18
27
2
12
19
3
14
19
4
11
20
5
12
22
17
26
16
18
8
18
26
14
22
10
14
24
Find a 98% confidence for the increase in TEWL.
Researchers have recently hypothesized that patients with myotonic dystrophy (a neuromuscular disease) also have hyperparathyroidism, a syndrome caused by an overactive parathyroid gland. To test this hypothesis, they measured the body’s response to a calcium challenge in patients with myotonic dystrophy, patients with other types of dystrophy (nonmyotonic dystrophy), and normal subjects. One of the biochemical variables they measured was the amount of cAMP excreted by the kidneys. Elevated renal cAMP excretion would be consistent with hyperparathyroidism.
The data is contained in the screenshot, where two variables are listed:
cAMP – Amount of cAMP excreted by the kidneys, measured in nmol/dL.
patient – A factor defining the clinical status of the patient, with three levels:
1, Normal Patient in control group, with no disease.
2, Myotonic Patient with myotonic dystrophy.
3, Nonmyotonic Patient with nonmyotonic dystrophy.
(a) Perform an analysis of variance calculation to test the…
Chapter 8 Solutions
Fundamentals of Biostatistics
Ch. 8 - Find the lower 2.5th percentile of an F...Ch. 8 - The mean 1 sd of ln [calcium intake (mg)] among 25...Ch. 8 - The mean 1 sd of ln [calcium intake (mg)] among 25...Ch. 8 - The mean 1 sd of ln [calcium intake (mg)] among 25...Ch. 8 - The mean 1 sd of ln [calcium intake (mg)] among 25...Ch. 8 - The mean 1 sd of ln [calcium intake (mg)] among 25...Ch. 8 - The mean 1 sd of ln [calcium intake (mg)] among 25...Ch. 8 - The mean 1 sd of ln [calcium intake (mg)] among 25...Ch. 8 - The mean 1 sd of ln [calcium intake (mg)] among 25...Ch. 8 - The mean 1 sd of ln [calcium intake (mg)] among 25...
Ch. 8 - The mean 1 sd of ln [calcium intake (mg)] among 25...Ch. 8 - The mean 1 sd of ln [calcium intake (mg)] among 25...Ch. 8 - The mean 1 sd of ln [calcium intake (mg)] among 25...Ch. 8 - Refer to the data in Table 2.13. Table 2.13...Ch. 8 - Refer to the data in Table 2.13. What is the...Ch. 8 - Refer to the data in Table 2.13. Perform the...Ch. 8 - Refer to the data in Table 2.13. What is the...Ch. 8 - Refer to the data in Table 2.13. Compute a 95% CI...Ch. 8 - The drug diflunisal is used to treat mild to...Ch. 8 - The drug diflunisal is used to treat mild to...Ch. 8 - The drug diflunisal is used to treat mild to...Ch. 8 - The drug diflunisal is used to treat mild to...Ch. 8 - A study in Pittsburgh measured various...Ch. 8 - A study in Pittsburgh measured various...Ch. 8 - A 1980 study was conducted whose purpose was to...Ch. 8 - A 1980 study was conducted whose purpose was to...Ch. 8 - A 1980 study was conducted whose purpose was to...Ch. 8 - A camera has been developed to detect the presence...Ch. 8 - A camera has been developed to detect the presence...Ch. 8 - A camera has been developed to detect the presence...Ch. 8 - Prob. 31PCh. 8 - Prob. 32PCh. 8 - Prob. 33PCh. 8 - A possible important environmental determinant of...Ch. 8 - A possible important environmental determinant of...Ch. 8 - A possible important environmental determinant of...Ch. 8 - A possible important environmental determinant of...Ch. 8 - Prob. 38PCh. 8 - The degree of clinical agreement among physicians...Ch. 8 - The degree of clinical agreement among physicians...Ch. 8 - The degree of clinical agreement among physicians...Ch. 8 - The degree of clinical agreement among physicians...Ch. 8 - The degree of clinical agreement among physicians...Ch. 8 - Ten patients with advanced diabetic nephropathy...Ch. 8 - Ten patients with advanced diabetic nephropathy...Ch. 8 - Ten patients with advanced diabetic nephropathy...Ch. 8 - Ten patients with advanced diabetic nephropathy...Ch. 8 - A study was conducted of genetic and environmental...Ch. 8 - A study was conducted of genetic and environmental...Ch. 8 - Prob. 51PCh. 8 - Prob. 52PCh. 8 - Prob. 53PCh. 8 - Prob. 54PCh. 8 - Prob. 55PCh. 8 - Prob. 56PCh. 8 - Prob. 57PCh. 8 - Prob. 58PCh. 8 - Prob. 59PCh. 8 - Prob. 60PCh. 8 - Prob. 61PCh. 8 - Prob. 62PCh. 8 - Prob. 63PCh. 8 - A study was conducted [12] comparing muscle...Ch. 8 - Prob. 65PCh. 8 - A clinical trial compared percutaneous...Ch. 8 - Prob. 68PCh. 8 - Prob. 69PCh. 8 - An experiment was conducted to examine the...Ch. 8 - An experiment was conducted to examine the...Ch. 8 - An experiment was conducted to examine the...Ch. 8 - Prob. 73PCh. 8 - Prob. 74PCh. 8 - Prob. 75PCh. 8 - Prob. 77PCh. 8 - A study was performed looking at the effect of...Ch. 8 - A study was performed looking at the effect of...Ch. 8 - A study was performed looking at the effect of...Ch. 8 - Prob. 81PCh. 8 - Prob. 82PCh. 8 - Prob. 83PCh. 8 - Tennis elbow is a painful condition that afflicts...Ch. 8 - Prob. 85PCh. 8 - Prob. 86PCh. 8 - Prob. 87PCh. 8 - Prob. 88PCh. 8 - A study compared mean electroretinogram (ERG)...Ch. 8 - A study compared mean electroretinogram (ERG)...Ch. 8 - A study compared mean electroretinogram (ERG)...Ch. 8 - A study compared mean electroretinogram (ERG)...Ch. 8 - A study compared mean electroretinogram (ERG)...Ch. 8 - Prob. 94PCh. 8 - Prob. 95PCh. 8 - Prob. 96PCh. 8 - Prob. 98PCh. 8 - A study was performed to determine the effect of...Ch. 8 - A study was performed to determine the effect of...Ch. 8 - A study was performed to determine the effect of...Ch. 8 - A study was performed to determine the effect of...Ch. 8 - A study is being planned to assess whether a...Ch. 8 - A study is being planned to assess whether a...Ch. 8 - Prob. 105PCh. 8 - Prob. 106PCh. 8 - Left ventricular mass (LVM) is an important risk...Ch. 8 - Left ventricular mass (LVM) is an important risk...Ch. 8 - Prob. 109PCh. 8 - Prob. 110PCh. 8 - Prob. 111PCh. 8 - A study sought to demonstrate that soy beans...Ch. 8 - Prob. 113PCh. 8 - A study sought to demonstrate that soy beans...Ch. 8 - study was recently reported comparing the effects...Ch. 8 - study was recently reported comparing the effects...Ch. 8 - study was recently reported comparing the effects...Ch. 8 - study was recently reported comparing the effects...Ch. 8 - The Diabetes Prevention Study was a randomized...Ch. 8 - Prob. 122PCh. 8 - Prob. 123PCh. 8 - Prob. 124PCh. 8 - Prob. 125PCh. 8 - Prob. 126PCh. 8 - Prob. 127PCh. 8 - A study looked at the influence of retirement on...Ch. 8 - Cigarette smoking has important health...Ch. 8 - Cigarette smoking has important health...Ch. 8 - Cigarette smoking has important health...Ch. 8 - Cigarette smoking has important health...Ch. 8 - Cigarette smoking has important health...Ch. 8 - Prob. 134PCh. 8 - Prob. 135PCh. 8 - Prob. 136PCh. 8 - Prob. 137PCh. 8 - Prob. 138PCh. 8 - Prob. 142PCh. 8 - Prob. 143PCh. 8 - Prob. 144PCh. 8 - Prob. 145PCh. 8 - A study of genetic factors related to coronary...Ch. 8 - A study of genetic factors related to coronary...Ch. 8 - A study of genetic factors related to coronary...Ch. 8 - Prob. 149PCh. 8 - Prob. 150PCh. 8 - Prob. 151PCh. 8 - Prob. 152PCh. 8 - Prob. 153PCh. 8 - Prob. 154PCh. 8 - Prob. 155PCh. 8 - An individual has been exercising at a local gym...Ch. 8 - Prob. 157PCh. 8 - Suppose we have two groups with sample sizes of 8...Ch. 8 - Suppose we have two groups with sample sizes of 8...Ch. 8 - Suppose we have two groups with sample sizes of 8...Ch. 8 - In a 5-year follow-up of bilateral stimulation of...Ch. 8 - In a 5-year follow-up of bilateral stimulation of...Ch. 8 - In a 5-year follow-up of bilateral stimulation of...Ch. 8 - The following data are from a study on Botox...Ch. 8 - The following data are from a study on Botox...Ch. 8 - Prob. 166PCh. 8 - Prob. 167PCh. 8 - Prob. 168PCh. 8 - The EPIC-Norfolk study, a study of diet and cancer...Ch. 8 - Prob. 170PCh. 8 - Prob. 171PCh. 8 - Prob. 172PCh. 8 - Prob. 173PCh. 8 - Prob. 174PCh. 8 - Prob. 175PCh. 8 - Prob. 176P
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, statistics and related others by exploring similar questions and additional content below.Similar questions
- Neutropenia. Neutropenia is an abnormally low number of neutrophils (a type of white blood cell) in the blood. Chemotherapy often reduces the number of neutrophils to a level that makes patients susceptible to fever and infections. G. Bucaneve et al. published a study of such cancer patients in the paper “Levofloxacin to Prevent Bacterial Infection in Patients With Cancer and Neutropenia” (New England Journal of Medicine, Vol. 353, No. 10, pp. 977–987). For the study, 375 patients were randomly assigned to receive a daily dose of levofloxacin, and 363 were given placebo. In the group receiving levofloxacin, fever was present in 243 patients for the duration of neutropenia, whereas fever was experienced by 308 patients in the placebo group. a. At the 1% significance level, do the data provide sufficient evidence to conclude that levofloxacin is effective in reducing the occurrence of fever in such patients? b. Find a 98% confidence level for the difference in the proportions of such…arrow_forwardYoung Adults at Risk. Research by R. Pyhala et al. shows that young adults who were born prematurely with very low birth weights (below 1500 grams) have higher blood pressure than those born at term. The study can be found in the article, “Blood Pressure Responses to Physiological Stress in Young Adults with Very Low Birth Weight” (Pediatrics, Vol. 123, No. 2, pp. 731–734). The researchers found that systolic blood pressures of young adults who were born prematurely with very low birth weights have mean 120.7 mm Hg and standard deviation 13.8 mm Hg. a. Identify the population and variable. b. For samples of 30 young adults who were born prematurely with very low birth weights, find the mean and standard deviation of all possible sample mean systolic blood pressures. Interpret your results in words. c. Repeat part (b) for samples of size 90.arrow_forwardThe purpose of a study was to determine the effectiveness of segmental wire fixation in athletes with spondylolysis. Between 1993 and 2000, 20 athletes (6 women and 14 men) with lumbar spondylolysis were treated surgically with the technique. The following table gives the Japanese Orthopaedic Association (JOA) evaluation score for lower back pain syndrome for men and women prior to the surgery. The lower score indicates less pain. Assume that the two populations of pain scores are normally distributed with equal variances. Gender JOA scores Female 14, 13, 24, 21, 20, 21 Male 21, 26, 24, 24, 22, 23, 18, 24, 13, 22, 25, 23, 21, 25 What is the pooled variance? (Answer was calculated using 3 decimals places for intermediate steps.)arrow_forward
- The purpose of a study was to determine the effectiveness of segmental wire fixation in athletes with spondylolysis. Between 1993 and 2000, 20 athletes (6 women and 14 men) with lumbar spondylolysis were treated surgically with the technique. The following table gives the Japanese Orthopaedic Association (JOA) evaluation score for lower back pain syndrome for men and women prior to the surgery. The lower score indicates less pain. Assume that the two populations of pain scores are normally distributed with equal variances. Gender JOA scoresFemale 14, 13, 24, 21, 20, 21Male 21, 26, 24, 24, 22, 23, 18, 24, 13, 22, 25, 23, 21, 25 What is the upper AND lower bound of a 90% confidence interval for the difference in means? (Hint: Use Female – Male)arrow_forwardPatients immobilized for a substantial amount of time can de flop deep vein thrombosis (DVT), a blood clot in a leg or pelvis vein. DVT can have serious adverse health effects and can be difficult to diagnose. On its website, drug manufacturer Pfizer reports the outcome of a study looking at the effectiveness of the drug Fragmin (dalteparin) compared with that of a placebo in preventing DVT in immobilized patients. In a double-blind, multinational study, severely immobilized patients were randomly assigned to receive daily subcutaneous injections of either Fragmin or a placebo for 12 to 14 days and were followed for 90 days. The results, in number of patients experiencing a complication from DVT (including death), are summarized in the table below. Treatment outcome Complication No complication Drug Fragmin 42 1476 1518 Placebo 73 1400 1473 Find and interpret a 95% confidence interval for the ratio of the odds of a complication when taking Fragmin versus the odds of a complication when…arrow_forwardA randomized controlled trial was conducted to determine whether treatment with daily aspirin was more effective than placebo at preventing myocardial infarction (MI) (within 5 years). A total of 140 out of 11,140 subjects in the aspirin group experienced an MI, while 240 out of 11,040 subjects in the placebo group experienced an MI. The relative risk of MI comparing aspirin to placebo was calculated to be 0.58, and its 95% confidence interval ranged from 0.47 to 0.71. Which of the following can be concluded from these results? Question 4 options: On average, the risk of MI among subjects who used aspirin was 0.58 times the risk of MI among those on placebo. On average, aspirin reduced the risk of MI in this population by 58% when compared to placebo. Aspirin is almost certainly harmful to this population. Compared to placebo, aspirin did not reduce the risk of MI by a statistically significant amount.arrow_forward
- A study was conducted to examine the effect of heat and duration of stretching on the extensibility of hamstring muscles and their electromyographic responses to passive stretch in children with hypertonia and severe mental retardation. Twenty subjects were randomly assigned to the following four treatments with five subjects per treatment: (A) 10-second stretching, (B) 30-second stretching, (C) hot pack followed by 10-second stretching and (D) hot pack followed by 30-second stretching. The outcome measure is the increase in hamstring extensibility (Y) and the data are given in Table 4. Table 4 Treatment A B C D 0.07 -0.19 1.11 0.57 1.24 0.5 1.28 2.19 (b) Obtain the ANOVA table. Y 0.62 0.64 1.08 1.25 0.34 0.48 2.03 1.11 Consider a one-way ANOVA to study the effects of the four treatments. Denote μA to μD as the means of increase in hamstring extensibility under treatments A to D respectively. (a) Estimate the parameters for the ANOVA model. (d) Obtain 95% confidence interval for μA.…arrow_forwardA study was conducted to examine the effect of heat and duration of stretching on the extensibility of hamstring muscles and their electromyographic responses to passive stretch in children with hypertonia and severe mental retardation. Twenty subjects were randomly assigned to the following four treatments with five subjects per treatment: (A) 10-second stretching, (B) 30-second stretching, (C) hot pack followed by 10-second stretching and (D) hot pack followed by 30-second stretching. The outcome measure is the increase in hamstring extensibility (Y) and the data are given in Table 4. Table 4 Treatment A B C D 0.07 -0.19 1.11 0.57 1.24 0.5 1.28 2.19 Y 0.62 0.64 1.08 1.25 0.34 0.48 2.03 1.11 Consider a one-way ANOVA to study the effects of the four treatments. Denote μA to μD as the means of increase in hamstring extensibility under treatments A to D respectively. the 95% confidence interval for µ^ — µB. 1.12 0.64 1.08 1.79 (f) Estimate and comment on the contrast of the treatment…arrow_forwardA researcher hypothesizes that electrical stimulation of the lateral habenula will result in a decrease in food intake (in this case, chocolate chips) in rats. Rats undergo stereotaxic surgery and an electrode is implanted in the right lateral habenula. Following a ten day recovery period, rats (kept at 80 percent body weight) are tested for the number of chocolate chips consumed during a 10 minute period of time both with and without electrical stimulation. The testing conditions are counter balanced. Compute the appropriate t-test for the data provided below. Stimulation No Stimulation 12 8 7 7 3 4 11 14 8 6 5 7 14 12 7 5 9 5 10 8 a) What would be the null hypothesis and alternative hypothesis in this study? b) What is your tcrit? c) Is there a significant difference between the two groups? d) Interpret your answer. e) Write out your t-value in APA format. *ANSWER ALL PARTS OF THE QUESTION*arrow_forward
- A study was made of 413 children who were hospitalized as a result of motor vehicle crashes. Among 290 children who were not using seat belts, 60 were injured severely. Among 123 children using seat belts, 16 were injured severely (based on data from "Morbidity Among Pediatric Motor Vehicle Crash Victims: The Effectiveness of Seat Belts," by Osberg and Di Scala, American Journal of Public Health, Vol. 82, No. 3). For this problem we want to know, is there sufficient sample evidence to conclude, at the 0.05 significance level, that the proportion of severe injuries is higher for children not wearing seat belts? Let pi be the proportion of severe injuries among all children not wearing seatbelts and who were involved in crashes. Let p2 be the proportion of severe injuries among all children wearing seatbelts and who were involved in crashes. Which is the proper expression of Ho? Pi = P2 O Pi P2 Which is the proper expression of H1? O pi P2 Calculate p1 to 4 decimal places: Calculate p,…arrow_forwardAfter stinging its victim, the honeybee leaves behind the barbed stinger, poison sac and muscles that continue to pump venom into the wound. Visscher et al. (1996) compared the effects of two methods of removing the stinger left behind: scraping off with a credit card or pinching off with thumb and index finger. A total of 40 stings were induced on volunteers. Twenty were removed with the credit card method and 20 were removed with the pinching method. The size of the subsequent welt by each measurement came from two volunteers (both authors of the study), each of whom received one treatment 10 times on the one arm and the other treatment 10 times on the other arm. Pinching led to a slightly smaller average welt, but the difference between the methods was not significant. Does this study include a control group? Enter the number of the best answer choice from the options below Yes, the control group is the group receiving the credit card method. Yes, the control group is the…arrow_forwardAnna Fisher and colleagues (Fisher et al., 2014) predicted that kindergarten students should learn better in undecorated classrooms compared to decorated classrooms, because students should be less distracted in sparse classrooms without distractions such as posters, maps, children's artwork, etc. They had a group of 12 kindergarten age children participate in a science lesson in a classroom without decorations and a classroom with decorations. The students took a test on the material immediately after each lesson (scores range from 0 to 20). Below are the number of correct responses on both tests for each child. Do kindergarteners learn better in an undecorated compared to a decorated environment? Undecorated Decorated Subject (X1) (X2) 1 19 17 1. State the null and alternative 15 14 hypotheses using the appropriate 16 symbols. State whether the test is one- 15 or two-tailed 14 4 19 17 15 6. 2. State the degrees of freedom and 18 18 13 14 identify the critical value(s) at an alpha 8.…arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
- MATLAB: An Introduction with ApplicationsStatisticsISBN:9781119256830Author:Amos GilatPublisher:John Wiley & Sons IncProbability and Statistics for Engineering and th...StatisticsISBN:9781305251809Author:Jay L. DevorePublisher:Cengage LearningStatistics for The Behavioral Sciences (MindTap C...StatisticsISBN:9781305504912Author:Frederick J Gravetter, Larry B. WallnauPublisher:Cengage Learning
- Elementary Statistics: Picturing the World (7th E...StatisticsISBN:9780134683416Author:Ron Larson, Betsy FarberPublisher:PEARSONThe Basic Practice of StatisticsStatisticsISBN:9781319042578Author:David S. Moore, William I. Notz, Michael A. FlignerPublisher:W. H. FreemanIntroduction to the Practice of StatisticsStatisticsISBN:9781319013387Author:David S. Moore, George P. McCabe, Bruce A. CraigPublisher:W. H. Freeman
MATLAB: An Introduction with Applications
Statistics
ISBN:9781119256830
Author:Amos Gilat
Publisher:John Wiley & Sons Inc
Probability and Statistics for Engineering and th...
Statistics
ISBN:9781305251809
Author:Jay L. Devore
Publisher:Cengage Learning
Statistics for The Behavioral Sciences (MindTap C...
Statistics
ISBN:9781305504912
Author:Frederick J Gravetter, Larry B. Wallnau
Publisher:Cengage Learning
Elementary Statistics: Picturing the World (7th E...
Statistics
ISBN:9780134683416
Author:Ron Larson, Betsy Farber
Publisher:PEARSON
The Basic Practice of Statistics
Statistics
ISBN:9781319042578
Author:David S. Moore, William I. Notz, Michael A. Fligner
Publisher:W. H. Freeman
Introduction to the Practice of Statistics
Statistics
ISBN:9781319013387
Author:David S. Moore, George P. McCabe, Bruce A. Craig
Publisher:W. H. Freeman
Chi Square test; Author: Vectors Academy;https://www.youtube.com/watch?v=f53nXHoMXx4;License: Standard YouTube License, CC-BY