Fundamentals of Biostatistics
8th Edition
ISBN: 9781305268920
Author: Bernard Rosner
Publisher: Cengage Learning
expand_more
expand_more
format_list_bulleted
Videos
Textbook Question
Chapter 8, Problem 78P
A study was performed looking at the effect of physical activity on cognitive
Table 8.23 Mean difference from baseline (18-month score minus baseline score) among participants with mild cognitive impairment in the ADAS-Cog score*
*A negative change indicates improvement since high values on the testindicate worse cognitive function
What is the standard deviation of change in the control group?
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
In a study to determine if using low-intensity laser therapy reduces pain for orthodontic patients who are fitted with new braces, patients were randomly assigned to either a control group (who did not receive laser treatment) or an experimental group who did receive laser treatment.† The researchers found that the mean pain rating was lower for those in the laser treatment group than for those in the control group both two days and six days after receiving braces. The researchers used these data to determine if there was evidence to support the claim that the mean pain rating is lower for patients who receive the laser treatment.
Answer the four key questions.
Q, Question Type: Estimation or hypothesis testing?
estimationhypothesis testing
S, Study Type: Sample data or experiment data?
sample dataexperiment data
T, Type of Data: One variable or two? Categorical or numerical?
one categorical variableone numerical variable two categorical variablestwo numerical variables…
Does St. John wort (an herb) have a siginifact effect in treating major depression? A study looked at 340 adult outpatients suffering as measured by their HAM-Dscore, randomly assiging each subject to either a placebo, St.John's wort, or a second active treatment for comparison. The study found the diiference in treating major depression as measured by improvement in HAM-D scores between St.John's wort and the placebo was not statistically significant
This means that:
A. a difference this big could easily occur just by chance even if St. John's wort does not better than the placebo
B. We cannot make a 95 percent confidence statement
C.The placebo makes no difference in the subjects' depression
D. The study was badly designed
Does It Pay to Plead Guilty? The accompanying table summarizes randomly selected sample data for San Francisco defendants in burglary cases (based on data from “Does It Pay to Plead Guilty? Differential Sentencing and the Functioning of the Criminal Courts,” by Brereton and Casper, Law and Society Review, Vol. 16, No. 1). All of the subjects had prior prison sentences. Use a 0.05 significance level to test the claim that the sentence (sent to prison or not sent to prison) is independent of the plea. If you were an attorney defending a guilty defendant, would these results suggest that you should encourage a guilty plea?
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
- A Canadian study measuring depression level in teens (as reported in the Journal of Adolescence, vol. 25, 2002) randomly sampled 112 male teens and 101 female teens, and scored them on a common depression scale (higher score representing more depression). The researchers suspected that the mean depression score for male teens is higher than for female teens, and wanted to check whether data would support this hypothesis. What conclusion can you draw from the output? The data provide sufficient evidence to reject H0 and to conclude that the mean depression score for male teens is larger than that of female teens. The data provide sufficient evidence to conclude that male and female teens do not differ in mean depression score. The data do not provide sufficient evidence to conclude that the mean depression score of male teens is larger than that of female teens. The data do not provide sufficient evidence to reject H0, so we accept it, and conclude that male and female teens do…arrow_forwardRogers, Farlow, and colleagues (1998) conducted an experiment to investigate whether donepezil improved cognitive function in patients with mild to moderate Alzheimer’s disease (AD). A total of 1,775 patients were randomly assigned to treatment with either donepezil or a placebo (a look-alike pill with no pharmacological effect). Cognitive function, as measured by the Alzheimer’s Disease Assessment Scale (ADAS-cog), was significantly improved in patients taking donepezil compared with the placebo group at weeks 12, 18, and 24. [Source: Rogers, S. L., Farlow, M. R., Doody, R. S., et al. (1998). A 24-week, double-blind, placebo controlled trial of donepezil in patients with Alzheimer’s disease. Neurology, 50, 136–145.] In this experiment, the independent variable is , and the dependent variable is . The individuals who are in the control condition are typically referred to as the control group. Here, the control group consists of . is a construct that is being tested in this…arrow_forwardA case–control study of patients on antihypertensive drugs related an increased risk of myocardial infarction (MI) for patients using calcium channel blockers (Psaty, et al.,1995). In this study, cases were antihypertensive drug patients who had suffered a first fatal or nonfatal MI through 1993, and controls were antihypertensive patients, matched by demographic factors, who had not suffered a MI. Among the comparisons reported were patients receiving calcium channel (CC) blockers (with and without diuretics) and patients receiving β–blockers (with and without diuretics). Results of numbers of patient by drug/MI status combination are given in Table 1. Compute the odds ratio of suffering MI (CC blockers relative to β–blockers), and the corresponding 95% CI. Does it appear that calcium channel blockers are associated with higher odds (and thus probability) of suffering MI than β –blockers? Table 1: Observed cell counts for antihypertensive drug/MI data Occurrence of…arrow_forward
- Researchers were interested in comparing the long-term psychological effects on dieters who were on a high-carbohydrate, low-fat (LF) diet with those on a high-fat, low-carbohydrate (LC) diet. A total of 106 overweight and obese participants were randomly assigned to one of these two energy-restricted diets. At 52 weeks a total of 32 LC dieters and 33 LF dieters remained. Mood was assessed using a total mood disturbance score (TMDS), where a lower score is associated with a less negative mood. A summary of these results follows (image attached): (a) Is there a difference in the TMDS at Week 52? Test the null hypothesis that the dieters’ average mood in the two groups is the same. Use a significance level of 0.05. (b) Critics of this study focus on the specific LC diet (that is, the science) and the dropout rate. Explain why the dropout rate is important to consider when drawing conclusions from this study.arrow_forwardLandolt et al. (A-26) examined rates of posttraumatic stress disorder (PTSD) in mothers and fathers. Parents were interviewed 5 to 6 weeks after an accident or a new diagnosis of cancer or diabetes mellitus type I for their child. Twenty-eight of the 175 fathers interviewed and 43 of the 180 mothers interviewed met the criteria for current PTSD. Is there sufficient evidence for us to conclude that fathers are less likely to develop PTSD than mothers when a child is traumatized by an accident, cancer diagnosis, or diabetes diagnosis? Let alpha = 0.05arrow_forwardDowns and Abwender (2002) evaluated soccer players and swimmers to determine whether the routine blows to the head experienced by soccer players produced long term neurological deficits. In the study, neurological tests were administered to mature soccer players and swimmers and the results indicated significant differences. In a similar study, a researcher obtained the following data. Swimmers Soccer Players 10 7 8 4 7 9 9 3 13 7 7 6 12 a)Are the neurological test scores significantly lower for the soccer player than for the swimmers in the control groups? Use a one-tailed test with = .05. b)Compute the value of r² (percentage of variance accounted for) these data.arrow_forward
- Does posting calorie content for menu items affectpeople’s choices in fast-food restaurants? According to results obtained by Elbel, Gyamfi, and Kersh(2011), the answer is no. The researchers monitoredthe calorie content of food purchases for children andadolescents in four large fast-food chains before andafter mandatory labeling began in New York City. Although most of the adolescents reported noticing thecalorie labels, apparently the labels had no effect ontheir choices. Data similar to the results obtained showan average of M = 786 calories per meal with s =85 for n =100 children and adolescents before thelabeling, compared to an average of M = 772 calorieswith s = 91 for a similar sample of n = 100 after themandatory posting.a. Use a two-tailed test with a = .05 to determinewhether the mean number of calories after theposting is significantly different than before caloriecontent was posted.b. Calculate r2to measure effect size for the mean difference.arrow_forwardA RCT was published in JAMA in July 2016 to determine whether palliative care-led family meetings reduced the presence of anxiety and depression symptoms among family caregivers of patients with chronic critical illness, as compared to routine care. Researchers reported a difference in anxiety and depression symptoms (measured by the Hospital Anxiety and Depression Scale [HADS] symptom score) between the two arms of 0.8 over a 3-month period, with the P-value being 0.34. In the RCT described above, is the result statistically significant or not? Alpha was set at 0.05. Explain your answer.arrow_forwardIn a 2002 study conducted on 3000 Italian 15-year-old females, girls were asked how often they consume kaleeach week. Four years later, these answers were linked to the girls’ intelligence test scores as 19-year-olds. Thestudy found that girls who consume kale at least once a week scored higher on the intelligence test.Is this an experiment or an observational study? Explain. What is the explanatory variable? What is the response variable?arrow_forward
arrow_back_ios
arrow_forward_ios
Recommended textbooks for you
Glencoe Algebra 1, Student Edition, 9780079039897...AlgebraISBN:9780079039897Author:CarterPublisher:McGraw Hill
Glencoe Algebra 1, Student Edition, 9780079039897...
Algebra
ISBN:9780079039897
Author:Carter
Publisher:McGraw Hill
Hypothesis Testing using Confidence Interval Approach; Author: BUM2413 Applied Statistics UMP;https://www.youtube.com/watch?v=Hq1l3e9pLyY;License: Standard YouTube License, CC-BY
Hypothesis Testing - Difference of Two Means - Student's -Distribution & Normal Distribution; Author: The Organic Chemistry Tutor;https://www.youtube.com/watch?v=UcZwyzwWU7o;License: Standard Youtube License