Commonly Used Single-Subject Designs

• Time Series
• Interrupted Time Series
• Multiple Time Series
• “AB” Designs

These designs use different combinations of baseline (A) and treatment (B) conditions to try to determine whether an intervention or treatment worked.

• ABA: observe over a baseline period (A), give treatment and continue to observe (B) and withdraw treatment (A) and observe behavior to determine whether it returns to baseline.
  
  
• ABAB: Observe over baseline (A), give treatment (B), withdraw treatment (A), repeat treatment (B).
  
  
• ABAB-BC-B-BC: ABAB is the same as above, then you add an additional treatment (C) or component to see if it adds an aspect to B. This approach is called an interaction design because you want to see if different components of a treatment interact to produce a good/better clinical outcome.