What is the main limitation of this study? In 2009, investigators were interested in evaluating the relationship between physical activity and being overweight. Using BRFSS data, they found 100 participants in South Carolina. 69 of these participants were overweight, and the remaining 31 were not. The investigators found that 46 participants who were overweight reported low levels of physical activity. The investigators also determined that 22 participants who were not overweight reported high levels of physical activity. This type of study is expensive to carry out, and non-compliance of study participants must be dealt with in the analysis. The exposure and outcome were measured on study participants at the same time; therefore, temporality cannot be established.

What is the main limitation of this study? In 2009, investigators were interested in evaluating the relationship between physical activity and being overweight. Using BRFSS data, they found 100 participants in South Carolina. 69 of these participants were overweight, and the remaining 31 were not. The investigators found that 46 participants who were overweight reported low levels of physical activity. The investigators also determined that 22 participants who were not overweight reported high levels of physical activity. This type of study is expensive to carry out, and non-compliance of study participants must be dealt with in the analysis. The exposure and outcome were measured on study participants at the same time; therefore, temporality cannot be established.

Name: QUESTION 3What is the main limitation of this study?In 2009, investig
Uploaded: 2024-03-20T07:07:12.000Z
Channel: Bartleby
Description: QUESTION 3What is the main limitation of this study?In 2009, investigators were interested in evaluating the relationship between physical activity and being overweight. Using BRFSS data, they found100 participants in South Carolina. 69 of these par

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

See similar textbooks

Similar questions

Of all sports, football accounts for the highest incidence of concussion in the United States due to the large number of athletes participating and the nature of the sport. While there is general agreement that concussion incidence can be reduced by making rule changes and teaching proper tackling technique, there remains debate as to whether helmet design may also reduce the incidence of concussion. Rowson et al. (2014) report on a retrospective analysis of head impact data collected between 2005 and 2010 from eight collegiate football teams. Concussion rates for players wearing two types of helmets, Riddell VSR4 and Riddell Revolution, were compared. A total of 1,281,444 head impacts were recorded, from which 64 concussions were diagnosed. The relative risk of sustaining a concussion in a Revolution helmet compared with a VSR4 helmet was 46.1%. This study illustrates that differences in the ability to reduce concussion risk exist between helmet models in football. Although helmet…
Does the shape or color of a pain pill influence its effectiveness? Although logically it shouldn’t, whether we believe a drug will work does have a powerful effect on our perceptions (e.g., placebo effect). In this experiment, 4 groups of adult patients were given the same amount of Advil after dental surgery for pain relief, but the color and shape of the pill varied. Researchers hypothesized that an unusual shape or color would lead people to believe the pills were new and special and thus would expect them to be more effective than common round, white pills. Researchers also wanted to know if there is an interaction between shape and color what is the purpose and design of the study as well as the characteristics of the participants in the sample?
An important issue is whether there are racial differences in hypertension among children. We define hypertension as being above the 95th percentile for either systolic blood pressure (SBP) or diastolic blood pressure (DBP) among children of the same age, height, and sex. Since some of the children were observed at multiple visits, a GEE model was run of hypertension on ethnic group. There were three ethnic groups considered: Caucasian, African American, and Hispanic. The results among boys are given in Table 13.54. TABLE 13.54 Relationship between hypertension and ethnic group among 27,009 boys in the Pediatric Task Force Data Variable Regression Coefficient SE Intercept -2.07 0.026 African American 0.049 0.041 Hispanic 0.328 0.059 What is the estimated OR for hypertension comparing Hispanic boys vs. Caucasian boys? (Call this OR1.) What is a 95% CI for this estimate?
How to conduct an observational study on to answer the question: “Are males more likely than females to be dog owners? For example, “I went to the park during the hours of 2:00-4:00 pm on a Saturday afternoon. I observed 10 dog owners, two were female, eight were male. It appears that more females than males are dog owners.” Finally, your report should also include your study limitations—that is, what factors could be present that would make my conclusions incorrect?
In the early 1970s, a young man challenged an Oklahoma state law that prohibited the sale of 3.2% beer to males under age 21 but allowed its sale to females in the same age group. The case (Craig v. Boren, 429 U.S. 190, 1976) was ultimately heard by the U.S. Supreme Court. The state of Oklahoma argued that the law improved traffic safety. One of the three main pieces of data presented to the court was the result of a “random roadside survey.” This survey gathered information on gender and whether or not the driver had been drinking alcohol in the previous 2 hours. A total of 619 drivers under 21 years of age were included in the survey. The chi-square test statistic is approximately 1.64 for this data. Find the P-value State a conclusion at a 5% level of significance. Do you think that the data supports the Oklahoma law that forbids sale of 3.2% beer to males and permits it to females? See image.
What was the power for this study?
The Bureau of Labor Statistics reports that the official unemployment rate for Black people was 10.4% and 4.7% for White people in February 2015. Select all correct answers for this question. O The samples of white and black people are independent. The explanatory variable is the unemployment rate. The response variable is the unemployment rate. The response variable is race.
Identifying individuals with a high risk of Alzheimer’s disease usually involves a long series of cognitive tests. However, researchers have developed a 7-Minute Screen, which is a quick and easy way to accomplish the same goal. The question is whether the 7-Minute Screen is as effective as the complete series of tests. To address this question, Ijuin et al. (2008) administered both tests to a group of patients and compared the results. The following data represent results similar to those obtained in the study. Scores in 7minute-screen (Y) Scores in Cognitive series (X) 0 11 4 19 6 22 8 20 5 14 4 13 A) Calculate the Pearson correlation for these data. B) If the researchers centered the variable of 7-minute screen (i.e., every score in this variable minus its Mean), what would be the new value of correlation? C) Is the correlation statistically significant? Use a two-tailed test with α = .05.
These 2 questions go hand to hand
Identifying individuals with a high risk of Alzheimer's disease usually involves a long series of cognitive tests. However, researchers have developed a 7-Minute Screen, which is a quick and easy way to accomplish the same goal. The question is whether the 7-Minute Screen is as effective as the complete series of tests. To address this question, Ijuin et al. (2008) administered both tests to a group of patients and compared the results. The following data represent results similar to those obtained in the study. 7-Minute Screen Cognitive Series 3 11 8 19 10 22 8 20 4 14 7 13 4 9 5 20 14 25 Which statistical test would you select: Answer H0: Answer H1: Answer What is the coefficient that indicates the strength of the relationship? Answer =Answer What is the standard error? Answer What is the appropriate 95% CI? [ Answer , Answer ] What is the d-effect size? Answer What is the t-observed? Answer What is the actual p-value? Answer THREE decimal places…
Why is Data literacy important when evaluating sources from a study?
Acne is a common skin disease that affects most adolescents and can continue into adulthood. A study compared the effectiveness of three acne treatments and a placebo, all in gel form, applied twice daily for 12 weeks. The study's 517 teenage volunteers were randomly assigned to one of the four treatments. Success was assessed as clear or almost clear skin at the end of the 12 week period. The results of the study can be seen in the table below. Using the appropriate statistical test, determine if there is significant evidence that the four treatments perform differently. If so, how do they compare.