Advantages & Disadvantages of Single-Case Designs

Ease of Implementation

• The single-case research design is very cost-effective because it involves fewer subjects and less time spent laying out all combinations of experimental variables in their own separate groups. It is therefore cost-effective and ideally suited to exploratory research.

Illustrates Dramatic Changes

• The single-case design is useful to demonstrate instances where introduction of a treatment produces dramatic change. Examples include hair-growth treatments, medications for mental-health problems and anti-allergy treatments. Results can be explained in great detail with careful attention paid to research subjects.

Lack of Controls

• It's hard to tell in a single-case design whether variables extraneous to the experiment are influencing the outcome. In more complicated research designs, these effects can be measured and controlled in their own experimental groups, but in single-case design, any number of factors could influence results.

Limited Application

• In a single-case design, an experimenter can generalize results only to other similar individuals. In group designs, results can be generalized from the sample to the population from which it is drawn.