Question

PLEASE ANSWER ALL 4 QUESTIONS

A study showed that not having enough Vitamin D in the one’s body is associated with having hypertension. Some of the participants in the study were known to have hypokalemia (too much potassium in the blood). Note that people with hypokalemia also have hypertension. Does the study show that lack of Vitamin D in the blood causes hypertension?

(0.5 pts.) a) What is the explanatory variable in this study?
The person has hyperkalemia.
The person has hypertension.
There is not enough vitamin D in the person's blood.

(0.5 pts.) b) What is the response variable in this study?
There is not enough vitamin D in the person's blood.
The person has hyperkalemia.
The person has hypertension.

(0.5 pts.) c) What is the lurking variable in this study?
The person has hyperkalemia.
There is not enough vitamin D in the person's blood.
The person has hypertension.

(1 pt.) d) Draw a diagram that explains your answers. (Possible diagrams are causation, common response, or confounding). Be sure to label all variables in the diagram.

Answer 1

a) There is not enough vitamin D in the person's blood.

   We are trying to find out whether Vitamin D levels cause hypertension. So Vitamin D levels is explaining the variable Hypertension.

b) From the above argument, it clearly follows the response variable is The person has hypertension.

c) The variable The person has hyperkalemia is the lurking variable. This is because it's not included in the analysis as a response or an explanatory variable, however it could still influence the relationship between The person has hypertension and There is not enough vitamin D in the person's blood.

d) We can draw a confounding diagram.