Problem: Experimental research is used when testing a specific hypothesis that looks for a causal relationship and when variables can be ethically manipulated. Nonexperimental research may be used in the following ways if experimental conditions are not met. When testing only one variable, not a relationship between variables. When you are not testing for a causal relationship between variables. When the independent variable cannot be manipulated, or conditions cannot be randomly applied to participants. When using a broader hypothesis or research question. The research question is typically the determining factor of whether to use experimental or nonexperimental research approaches. Sometimes both approaches may be used to research the same hypothesis. For example, the questions of whether or not watching violence on the television causes aggression can be researched in an experimental and nonexperimental way.