Denny studied the effect of postural change on cardiovascular reactivity in a sample of healthy men and women. Change in systolic blood pressure (SBP) from supine to standing position was used as the measure of cardiac reactivity in a sample of 842 adults. Supine measurement of blood pressure was taken after participants had lain on an examination table for 15 minutes. Blood pressure was determined every 20 seconds using a Dinamap device for 2 minutes, and the 6 measurements were averaged. Participants then stood up immediately, and additional measurements were made for another 2 minutes. Below is a table describing the characteristics of Denny’s sample.

Table 1. Characteristics of the Study Sample (N = 842)

 

Short Answer Questions

a. Which variables in the table, if any, were measured on a nominal scale?

b. Which variables in the table, if any, were measured on an ordinal scale?

c. Which variables in the table, if any, were measured on an interval scale?

d. Which variables in the table, if any, were measured on a ratio scale?

e. Which measure(s) of central tendency, if any, are presented in this table?

f. Which measure(s) of variability, if any, are presented in this table?

g. If age were normally distributed, approximately what percentage of the sample would be younger than 50?

h. If BMI were normally distributed, approximately what percentage of the sample would have a BMI higher than 33?

Sample Characteristic Frequency (N) Percentage or Mean Range (SD) Gender 408 48.5% Female 434 51.5% Male Age (years) 842 55.1 (5.3) 44-67 60 and older 101 16.2% Racelethnicity 701 83.3% White, not Hispanic 141 16.7% African American Smoking status 698 82.9% Nonsmoker 91 10.8% Smokes 1 pack/day BMI 831 24.9 (4.1) 18.136.3 >25 (overweight) 295 35.5%