In autumn 2022, Jamshed and colleagues published a study in JAMA Internal Medicine where they studied...

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In autumn 2022, Jamshed and colleagues published a study in JAMA Internal Medicine where they studied the effect of intermittent fasting on weight loss in 90 adults who were already receiving treatment for obesity. Half (the control group, nl-45) only received advice about diet and exercise, while the other half (the intervention group, n2=45) were also asked to only eat between 7am and 3pm. After 14 weeks, the weight reduction was 6.3kg in the intervention group and 4.0kg in the control group. The standard error for the weight reduction was 0.55kg in both groups. a. Use the t-table to construct a 95% confidence interval for the weight reduction in each group. Show calculations. b. C. d. e. f. g. Perform a t-test for weight reduction in the control group. Use a 5% significance level. What is H0? What is H1? What is the conclusion? What is the standard deviation of the weight reduction in each group? Show calculations. What would happen to the standard deviation of the weight reduction if we had increased the number of people in each group? What would happen to the standard error? Explain (<50 words). Show that the pooled standard deviation for the difference between the two groups is 3.69. Why wasn't this surprising? Explain (<100 words). What is the common standard error of the difference between the two groups? Show calculations. Perform a t-test for the difference between the two groups. Use a 5% significance level. What is HO? What is H1? What is the conclusion? In autumn 2022, Jamshed and colleagues published a study in JAMA Internal Medicine where they studied the effect of intermittent fasting on weight loss in 90 adults who were already receiving treatment for obesity. Half (the control group, nl-45) only received advice about diet and exercise, while the other half (the intervention group, n2=45) were also asked to only eat between 7am and 3pm. After 14 weeks, the weight reduction was 6.3kg in the intervention group and 4.0kg in the control group. The standard error for the weight reduction was 0.55kg in both groups. a. Use the t-table to construct a 95% confidence interval for the weight reduction in each group. Show calculations. b. C. d. e. f. g. Perform a t-test for weight reduction in the control group. Use a 5% significance level. What is H0? What is H1? What is the conclusion? What is the standard deviation of the weight reduction in each group? Show calculations. What would happen to the standard deviation of the weight reduction if we had increased the number of people in each group? What would happen to the standard error? Explain (<50 words). Show that the pooled standard deviation for the difference between the two groups is 3.69. Why wasn't this surprising? Explain (<100 words). What is the common standard error of the difference between the two groups? Show calculations. Perform a t-test for the difference between the two groups. Use a 5% significance level. What is HO? What is H1? What is the conclusion?

Answer rating: 100% (QA)

a To construct a 95 confidence interval for the weight reduction in each group we can use the formula CI X tSE where X is the sample mean SE is the standard error and t is the tvalue from the ttable f... View the full answer