TRUE-EXPERIMENTAL DESIGNS

TRUE-EXPERIMENTAL DESIGNS must employ the following:

• Random selection of subjects
  
• Use of control groups
  
• Random assignments to control and experimental groups
  
• Random assignment of groups to control and experimental conditions

In order for an experiment to follow a true-experimental design, it must meet the preceding criteria. There is some variation in true-experimental designs, but that variation comes in the time(s) that the treatment is given to the experimental group, or in the observation or measurement (pre-test, post-test, mid-test) area.

Advantages of the true-experimental design include:

• Greater internal validity
  
• Causal claims can be investigated
  

Disadvantages:

• Less external validity (not like real world conditions)
  
• Not very practical