In addition to the in-school milk supplement program, the nurse would like to increase the use of daily vitamin supplements for the children by visiting homes and educating about the merits of vitamins. She believes that currently, about 50% of families with school-age children give the children a daily megavitamin. She would like to increase this to 70%. She plans a two-group study, where one group serves as a control and the other group receives her visits. How many families should she expect to visit to have 80% power of detecting this difference? Assume that drop-out rate is 5%.

In addition to the in-school milk supplement program, the nurse would like to increase the use of daily vitamin supplements for the children by visiting homes and educating about the merits of vitamins. She believes that currently, about 50% of families with school-age children give the children a daily megavitamin. She would like to increase this to 70%. She plans a two-group study, where one group serves as a control and the other group receives her visits. How many families should she expect to visit to have 80% power of detecting this difference? Assume that drop-out rate is 5%.

Holt Mcdougal Larson Pre-algebra: Student Edition 2012

1st Edition

ISBN:9780547587776

Author:HOLT MCDOUGAL

Publisher:HOLT MCDOUGAL

Chapter6: Ratio, Proportion, And Probability

Section: Chapter Questions

Problem 4CR

See similar textbooks

Similar questions

You read a study about how opioid addiction can only be treated by addiction centers. It was paid for by some addiction recovery centers. It was done by looking at 14 of their patients. Do you think this a valid study?Explain your answer.
New research on the effects of social media usage has been mixed. Some studies have found that social media helps people stay connected to others, and can be a positive source of social support. Other studies have found that social media makes people feel lonely and unhappy. I decide to do my own study to see whether social media has an effect on how many close friends people have. I conduct an internet survey of 1000 people and ask them how many hours a week they spend on social media and how many close friends they have. In the study respondents spent 10 hours a week using social media, and had 4 close friends, on average. The standard deviations for social media usage and close friends were 4 hours and 2 friends, respectively. The correlation (r) between social media and friends was -.3.
The medical researcher is comparing two treatments for fighting a common cold: Zinc and Vitamin C. The researcher wants to see if the patients who take Zinc have less success fighting the common cold compared to a patients taking vitamin C. Arandom sample of some patients who take Zinc and others who took Vitamin C. The results of how many felt better the following day after experiencing symptoms of the common cold: Data on Symptoms from Taking Zinc and Vitamin C for the Common Cold Vitamin Zinc Less 342 Symptoms 553 No 225 319 Difference What can be concluded at the a = 0.05 level of significance? For this study, we should use z-test for the difference between two population proportions a. The null and alternative hypotheses would be: Ho: p1 Select an answer v p2 H1: p1 Select an answer v p2 b. The test statistic ?v = (please round your answer to 3 decimal places.) c. The p-value = (Please round your answer to 4 decimal places.) d. The p-value is [? v a e. Based on this, we should…
In this assignment, you will calculate the relative risk, attributable risk, and number needed to treat for a contrived clinical research study. In the study, researchers want to determine whether a new drug will reduce the risk of blood clotting in patients who have been diagnosed with blood clots in the past. 2,000 participants were selected for the study. 1,000 participants were given the new drug, and 1,000 participants were given a placebo. After 5 years, the number of participants from each group who had developed a blood clot were recorded. The data is shown in the table below. 1. Calculate the RR, ARR, and NNT for the data. 2. Briefly interpret each value in your own words. Blood clot No blood clot Total New drug 21 979 Placebo 45 955 Total
An investigator wants to assess whether smoking is a risk factor for pancreatic cancer. Electronic medical records at a local hospital will be used to identify fifty patients with pancreatic cancer. One hundred patients who are similar but free of pancreatic cancer will also be selected. Each participant’s medical record will be analyzed for smoking history. Identify the type of study proposed. Briefly explain why you think the study is of this type. Indicate the study type's specific strengths and weaknesses. What is the most likely source of bias in the study .
The Federal Bureau of Investigation reports state-level and national data on crimes. An investigator compares the incidence of crime in the United States in 1991 and in 2001. In 1991, there were 28,000 crimes compared with 22,000 in 2001. Can you conclude that the US became more law-abiding over that time period?
A 4x2x3 ANOVA was conducted. How many main effects should be tested? Answer Choices: 2 3 4 0 A 4x2x3 ANOVA was conducted. How many total interactions should be tested? Answer Choices: 2 3 1 4
With the pandemic, cleaning and sanitation products have become increasingly more popular. Pfizer is trying to expand their sales and market share among producers of hand sanitizer and would like to purchase advertising space on a major TV network during prime time. CBS and NBC seem to be the most likely options but Pfizer would like to test and see if there is really a difference in the viewership (which would influence their decision). Over the past 20 weeks, CBS has averaged 5.7 million viewers on Monday nights at the 8 PM timeslot with a standard deviation of .65 million viewers. NBC on the other hand has averaged 6.2 million viewers with a standard deviation of 1.3 million viewers. With an alpha of .05, construct a hypothesis test to see if there is a difference in viewership between the two networks. Construct a 95% confidence interval for the difference.
Numerous studies have shown that watching too much television hurts children’s school grades. Others have argued that television is not necessarily a bad thing for children (Mail Online; July 2009). Like books and stories, television not only entertains, it also exposes a child to new information about the world. While watching too much TV is harmful, a little bit may actually help. Suppose a researcher gathers information on the grade point average (GPA) of 28 middle school children and the number of hours of TV they watch per week. GPA Hours TV 3.24 19 3.1 21 3.24 18 2.61 30 3.03 23 3.37 10 1.6 36 3.2 10 2.96 13 2.18 31 2.5 33 2.95 4 2.72 25 3.05 21 3.45 8 2.49 27 3.62 11 2.33 29 2.36 30 3.28 10 3.35 15 2.64 18 2.88 24 2.02 29 2.6 22 3.18 21 3.31 4 a. Estimate a quadratic regression model where the GPA of…
Methadone is a synthetic drug whose effect on the body is similar to that of morphine and heroin. Methadone has been used to help people control their addictions to these other drugs. The following histogram summarizes information from a study of 35 Methadone clinic patients. In the study, the daily dosage for each Methadone clinic patient was recorded.
The billing department at a local hospital wants to improve its performance. After surveying its patients, they realized the main complaint was about billing errors. The management went back and reviewed their last year's bills. They took about 100 bills for each week of each month and checked for errors. See Excel file for data. Answer. a. Does the month of the year have an effect on the billing errors? b. What type of control chart would you should use? c. Is the billing process under statistical control? Use Minitab to support your answers.
What do people actually order at Chipotle? How healthy is a normal Chipotle meal? Chipotle and other relatively new fast casual chains like Shake Shack, Potbelly and Five Guys typically promote themselves as having healthier menu choices than the traditional fast food outlets like McDonald's, Taco Bell, Burger King, etc.The recommended daily calorie intake for most adults is 1,600 to 2,400. The histogram below shows the calories in approximately 3,000 meals ordered from Chipotle on Grubhub.While the histogram is not perfectly symmetric (there is mild right skewness), it is close enough to being symmetric and bell-shaped to justify using the 68-95-99.7 rule. Suppose the distribution of calories in a Chipotle meal can be considered symmetric and bell-shaped with mean 1079 calories and standard deviation 296 calories. Use the 68-95-99.7 rule to answer the following questions.a. What is the approximate percentage of the Chipotle meals that have between 487 and 1671 calories?b. The middle…