The Journal of Medical Internet Research just published an article by CTBH Scientific Core Director Jesse Dallery, CTBH Affiliate Bethany Raiff, and Rachel Cassidy on the utility of single-case experiments to evaluate technology-based behavioral health interventions.
The article provides an overview of single-case designs, which include a family of methods in which each participant serves as his or her own control. In a typical study, some behavior or symptom is measured repeatedly during all conditions for all participants. The researcher or clinician systematically introduces and withdraws intervention and control conditions, and then measures the effects of the intervention on behavior across replications of these conditions within and across participants. As a result, the main features of these studies include repeated, frequent assessment of behavior, experimental manipulation of the independent variable, and replication of effects within and across participants.
The authors argue that there is an excellent fit between the logic of single-case designs and the data capture capabilities of technology. They also point out that single-case designs may obviate some logistical issues in using between-group designs to conduct initial efficacy testing. For example, prototypes of a new technology may be expensive and time consuming to produce. Similarly, troubleshooting and refining the hardware and software may entail long delays. Single-case experiments generally require less time and resources than group designs.
The article also reviews several misconceptions associated with single-case research (e.g., single-case does not mean “n of 1”). It additionally describes how single-case experiments can be used to evaluate behavioral mechanisms, or the processes by which a technology-based intervention affects behavior. The article ends with a discussion of the generality of treatment effects, how generality can be established through replication and analysis of behavioral mechanisms.
This article provides an example of a rigorous experimental design that may be used as an alternative to the standard randomized, controlled trial, which may be of considerable benefit in evaluating technology-based behavioral health interventions.
This full article is available for viewing at: http://www.jmir.org/2013/2/e22/