1. Random selection and assignment (true experimental designs require random assignment, but quasi-experiments do not)

   • Random selection involves drawing the sample from the population as a whole

   • Random assignment involves random assignment to experimental or control groups, where every participant has an equal opportunity to be selected

     • A blinding technique can be implemented to minimize bias. However, this may not always be feasible.

       • Single blinding – one party (either the participant or researcher is unaware of the assigned groups)

       • Double blinding – both the participant and researcher are unaware of which group is the experimental or control

       • Triple blinding – all parties, including the individuals analyzing the results are unaware of the treatment and control groups

2. Treatment and control groups

• The only expected difference between the experimental and control group is the dependent variable that is being studied

  • There can me multiple experimental groups

3. Treatment manipulation

• Independent and dependent variables. Researchers will manipulate the independent variable to see if this will affect the dependent variable

  • Provides the ability to determine the “cause” in the cause-effect relationship.

• The use of pre-test and post-test measures will determine the validity of the research outcomes