In considering multiple–baseline designs, an example from an actual study using one of the multiple–baseline forms would help. The value of this example, which involves the behavior–based form, also resides in two of its other characteristics.
As early behaviorological practitioners adapted ABAB/Reversal designs to applied settings, they faced increasingly complex applied situations requiring more sophisticated single–subject experimental designs. For example, sometimes the repetition of Baseline or Intervention phases would stand out as unethical or otherwise not possible.
In 1975 David Anderson and I worked on an applied study at the University of Queensland in Brisbane, Australia, which was when and where I began my college teaching career. This study contains some uncommon features worthy of attention, features that one would usually only find spread across several studies.
After considering the ABAB/Reversal type of single–subject designs for basic experimental research in a recent column, this column turns to similar designs for applied research and practice. In applied settings, research considerations differ from laboratory settings, and some compel the adoption of the more complicated “multiple–baseline” single–subject designs that a later column covers.
Disciplinary contingencies compelled the use of single–subject experimental designs throughout the history of natural behavior science. This started with the experimental preparations of Skinner’s early laboratory at Harvard in the 1930s and continues up through today’s laboratory and applied research efforts.
Living on the edge of a small town, I write this as a bright February sun illuminates nearby farm fields already devoid of snow. Deer pass through the unfenced yards between well–spaced homes in the twilight hours of morning and evening, tasting everything on their way to or from an undeveloped area at the center of the next block. One or another dog is always pulling an owner down the street. The resplendent view and clean air invite one to take a walk even without a pet, but a short distance in the stiff breeze, with the temperature below freezing, quickly compels a return to the warm side of the window with a cup of hot cocoa in hand.
