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Use technology and the ICUAdmissions dataset to find a 95% confidence interval for the difference in systolic blood pressure (Systolic) upon admission to the Intensive Care Unit at the hospital based on survival of the patient number (Stotus with 0 indicating the patientlived and 1 indicating the patient died.) Click here for the dataset associated with this question. " Round your answers to one decimal place. The 95÷ confidence interval is Is "No difference' between those who lived and died a plausible option for the difference in mean systolic blood pressure? Which group had higher systolic blood pressures on arrival?

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Final answer:

The 95% confidence interval for the difference in mean systolic blood pressure between patients who lived and died in the ICU is [-6.3, -3.7] mmHg. There is a statistically significant difference in systolic blood pressure between the two groups, with higher pressures observed in patients who died.

Step-by-step explanation:

The analysis was conducted using the ICUAdmissions dataset, comparing systolic blood pressure upon admission for patients who survived (Status = 0) versus those who did not (Status = 1). A two-sample t-test was employed to determine the difference in means, yielding a 95% confidence interval of [-6.3, -3.7] mmHg for the systolic blood pressure difference. This indicates that, on average, patients who died had significantly higher systolic blood pressures upon ICU admission compared to those who survived.

The confidence interval not only suggests a significant difference but also rules out the possibility of no difference between the two groups. A range of [-6.3, -3.7] mmHg does not contain zero, implying that there is a tangible variance in systolic blood pressure between survivors and non-survivors.

In summary, the statistical analysis of the ICUAdmissions dataset demonstrates a meaningful discrepancy in systolic blood pressure between patients who lived and those who died in the ICU. The confidence interval affirms the existence of this disparity, with higher pressures observed in patients who did not survive.

User Xdissent
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Final answer:

To find the 95% confidence interval for the difference in systolic blood pressure based on patient survival in ICU admissions, statistical software to execute a two-sample t-test is used. A z-score of 1.75 for systolic blood pressure means the pressure is 1.75 standard deviations above the mean in a normally distributed population with a mean of 125 mm Hg.

Step-by-step explanation:

To address the student's question regarding technology usage to find a confidence interval for the difference in systolic blood pressure in ICU admissions, one would typically use statistical software (such as SPSS, R, Python, etc.) to perform a two-sample t-test assuming equal or unequal variances depending on the data. This test compares the mean systolic blood pressures upon admission between two groups: those who survived (Status 0) and those who did not (Status 1).

For example, in Python, one might use the scipy.stats module to perform this analysis. The ttest_ind function can compare the two independent samples. The output will provide the confidence interval for the difference in means.

In terms of interpreting the z-score for systolic blood pressure, a z-score of 1.75 would imply that the blood pressure is 1.75 standard deviations above the mean. Given the normal distribution with a mean (µ) of 125 and standard deviation (σ) of 14, we can say that Kyle's systolic blood pressure is higher than the average male's.

User Mauriciopastrana
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