Single case design can rigorously test the success of an intervention and provide evidence of effectiveness using a relatively small sample size. It uses time—rather than a distinct group of people—as a control, comparing results during and after an intervention to the baseline period beforehand.
This brief outlines two classes of single case design options that may be appropriate for awardees of the Maternal, Infant, and Early Childhood Home Visiting Program:
- Withdrawal and reversal designs that rely on a reversal of behavior during the treatment withdrawal period
- Multiple baseline designs that examine three or more people, behaviors, or settings to pinpoint the effects of an intervention
It concludes with a section on other considerations, such as the need for substantial information on each participant before beginning an intervention and the need for behaviors to be repeatedly and rapidly measured.