Fundamentals of Biostatistics
Fundamentals of Biostatistics
8th Edition
ISBN: 9781305268920
Author: Bernard Rosner
Publisher: Cengage Learning
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Chapter 8, Problem 78P

A study was performed looking at the effect of physical activity on cognitive function among adults at high risk for Alzheimer’s disease (Lautenschlager et al. [14]). There were 170 eligible subjects randomly assigned to either an exercise intervention (exercise group) or a control intervention (control group). The subjects were followed at 6-month intervals up to 18 months of follow-up. The primary assessment scale was the Alzheimer’s Disease Assessment Scale-Cognitive Subscale (ADAS-Cog). The results at 18 months of follow-up among participants with mild cognitive impairment are given in Table 8.23.

Table 8.23 Mean difference from baseline (18-month score minus baseline score) among participants with mild cognitive impairment in the ADAS-Cog score*

Chapter 8, Problem 78P, A study was performed looking at the effect of physical activity on cognitive function among adults

*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?

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Chapter 8 Solutions

Fundamentals of Biostatistics

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
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