Question

in outcomes research, a number of variables may affect the results and some of those are controlled when individuals are recruited to participate. some of these variables include age, gender, and disease severity. what type of variables are these in outcome research?
independent variables
individual variables
control variables
dependent variables

Explanation:

In outcomes research, variables like age, gender, and disease - severity that are controlled during recruitment to not confound results are control variables. Independent variables are manipulated, dependent variables are the outcomes of interest, and "individual variables" is not a standard term in this context.

Answer:

C. control variables