Single-subject research
Encyclopedia
Single-subject research is a group of research methods that are used extensively in the experimental analysis of behavior
and applied behavior analysis
with both human and non-human participants. Four principal methods in this type of research are: changing criterion, reversal ("ABA"), alternating treatments, and multiple baseline. In verbal behavior research, the multipleprobe research design is popular.
These methods form the heart of the data collection and analytic code of behavior analysis. Behavior analysis is data driven, inductive, and disinclined to hypothetico-deductive methods. Statistical methods, from The Behavior of Organisms (Skinner, 1938) until now, have been largely ignored.
Further ethics notes: It may be unethical to end an experiment on a baseline measure if the treatment is self-sustaining and highly beneficial and/or related to health. Control condition participants may also deserve the benefits of research once all data has been collected. It is a researcher's ethical duty to maximize benefits and to ensure that all participants have access to those benefits when possible.
was first reported in 1960 as used in basic operant research. It was applied in the late 1960s to human experiments in response to practical and ethical issues that arose in withdrawing apparently successful treatments from human subjects. In it two or more (often three) behaviors, people or settings are plotted in a staggered graph where a change is made to one, but not the other two, and then to the second, but not the third behavior, person or setting. Differential changes that occur to each behavior, person or in each setting help to strengthen what is essentially an AB design with its problematic competing hypotheses.
Experimental analysis of behavior
The experimental analysis of behavior is the name given to the school of psychology founded by B.F. Skinner, and based on his philosophy of radical behaviorism. A central principle was the inductive, data-driven examination of functional relations, as opposed to the kinds of hypothetico-deductive...
and applied behavior analysis
Applied Behavior Analysis
Applied behavior analysis is a science that involves using modern behavioral learning theory to modify behaviors. Behavior analysts reject the use of hypothetical constructs and focus on the observable relationship of behavior to the environment...
with both human and non-human participants. Four principal methods in this type of research are: changing criterion, reversal ("ABA"), alternating treatments, and multiple baseline. In verbal behavior research, the multipleprobe research design is popular.
These methods form the heart of the data collection and analytic code of behavior analysis. Behavior analysis is data driven, inductive, and disinclined to hypothetico-deductive methods. Statistical methods, from The Behavior of Organisms (Skinner, 1938) until now, have been largely ignored.
AB research designs
The AB design is the simplest version of this design in which a baseline ("A") is tracked, and then some treatment ("B") is implemented. If there is a change then the treatment is said to have had an effect. However, it is subject to many possible competing hypotheses, making it a very weak research design. The other variants essentially introduce ways to control for the competing hypotheses.Changing-criterion research designs
In a changing-criterion research design a criterion for reinforcement is changed across the experiment to demonstrate the functional relationship between the reinforcement and the behavior. See Mark Dixon's work with a participant using a short video clip to generate a preference for a progressively delayed variable reinforcement over a fixed shorter delay reinforcement in physical therapy.Reversal or ABA designs
The reversal design is the most powerful of the single-subject research designs showing a strong reversal from baseline ("A") to treatment ("B") and back again. If the variable returns to baseline measure without a treatment then resumes its effects when reapplied, the researcher can have greater confidence in the efficacy of that treatment. However, many interventions cannot be reversed, some for ethical reasons (e.g., involving self-injurious behavior, smoking) and some for practical reasons (they cannot be unlearned, like a skill).Further ethics notes: It may be unethical to end an experiment on a baseline measure if the treatment is self-sustaining and highly beneficial and/or related to health. Control condition participants may also deserve the benefits of research once all data has been collected. It is a researcher's ethical duty to maximize benefits and to ensure that all participants have access to those benefits when possible.
Alternating-treatment designs
The alternating-treatment design is used in order to ascertain the comparative effect of two treatments. Two treatments are alternated in rapid succession and correlated changes are plotted on a graph to facilitate comparison.Multiple baseline designs
The multiple baseline designMultiple Baseline Design
A multiple baseline design is a style of research involving the careful measurement of multiple persons, traits or settings both before and after a treatment. This design is used in medical, psychological and biological research to name a few areas. It has several advantages over AB designs which...
was first reported in 1960 as used in basic operant research. It was applied in the late 1960s to human experiments in response to practical and ethical issues that arose in withdrawing apparently successful treatments from human subjects. In it two or more (often three) behaviors, people or settings are plotted in a staggered graph where a change is made to one, but not the other two, and then to the second, but not the third behavior, person or setting. Differential changes that occur to each behavior, person or in each setting help to strengthen what is essentially an AB design with its problematic competing hypotheses.
Multipleprobe designs
Popular in Verbal Behavior research, the multipleprobe research design has elements of the other research designs.See also
- Single-subject design
- N of 1 trialN of 1 trialAn N of 1 trial is a clinical trial in which a single patient is the entire trial, a single case study. A trial in which random allocation can be used to determine the order in which an experimental and a control intervention are given to a patient is an N of 1 randomized controlled trial...
- Applied behavior analysisApplied Behavior AnalysisApplied behavior analysis is a science that involves using modern behavioral learning theory to modify behaviors. Behavior analysts reject the use of hypothetical constructs and focus on the observable relationship of behavior to the environment...
- Verbal behavior
- B.F. Skinner