A nurse researcher wants to study the effects of yoga on blood pressure in hypertensive adults What is the independent variable What is the dependent variable What extraneous variables might exist?

Answer 1

The independent variable is yoga, and you might have various [experimental] groups that do the yoga differently from each other. The dependent variable is blood pressure. You would want to make sure that the different groups are as similar as possible in make-up so that any differences in blood pressure can be attributed to the yoga and not to something else. If one group is made up of 18 year old athletes and another group is made up of 60 year olds with a history of hypertension, you can see that differences between the groups could not clearly be attributed to differences in their experimental yoga practice. You could balance the groups in a few different ways. Maybe you could assign people to groups randomly from a large selection of people in the 'target' population. Or you could deliberately select persons for each group in a kind of 1 X 1 correspondence, based on specific characteristics that you want to match as closely as possible. You might want one or more control groups as well, to account for the placebo effect or other extraneous effects. A control group could come in, for example, and have all the same bp checks as the experimental groups, but perhaps get presentations on various topics; maybe they could be asked to come in for a pb check, be allowed to leave, and then return for a second check 1.5 hours later. There are various ways to do it.