A medical researcher is analyzing the blood pressure data of a group of patients participating in a clinical trial. She calculates the standard deviation of the systolic blood pressure measurements and finds it to be 12 mm Hg.
B) If the standard deviation were lower, it would suggest less variability in blood pressure measurements
A lower standard deviation indicates that the data points are closer to the mean, suggesting less variability. In this context, a standard deviation of 12 mm Hg means that most blood pressure measurements are within 12 mm Hg of the mean value.
Answer choice A: A higher standard deviation indicates that the blood pressure measurements are more consistent, is incorrect. A higher standard deviation indicates greater variability or inconsistency in the data, meaning the blood pressure measurements in this case vary more from the mean.
Answer choice C: Standard deviation cannot be calculated for blood pressure data, is incorrect. Standard deviation can be calculated for various types of data, including blood pressure data, to assess the degree of variability or consistency within the dataset.
Answer choice D: The standard deviation is a measure of central tendency in the data, is. Incorrect. The standard deviation does not measure central tendency; it measures the spread or variability of data points.
Answer choice E: The standard deviation measures the average blood pressure value in the group, is incorrect. The standard deviation is not a measure of central tendency (e.g., mean); it quantifies the dispersion or spread of data points around the mean.
Key Learning Point
Standard deviation is a statistical measure used to quantify the dispersion or spread of data points in a dataset. A lower standard deviation indicates less variability, while a higher standard deviation suggests greater variability. It is an essential tool for understanding the consistency and reliability of data.
