Vocabulary:
Single-subject design: (McMillan, p. 241) individual behavior recorded before and after an intervention, use one or just a few subjects to study the influence of a new procedure
Sentence: The researcher decided to use a single-subject design to observe the effect of a new diet on the beluga whale.
Withdrawal design: (McMillan, p. 242) treatment removed after implementation, so the subject is back to the baseline behavior
Sentence: The researcher were using a withdrawal design, since they planned to stop the treatment at the end of the study.
Multiple-baseline design: (McMillan, p. 243) more than one subject, behavior, or setting
Sentence: The design was a multiple-baseline design because the research was being done with many single-subjects simultaneously.
Reflection:
The Advantages of Single-Subject Research Methods
Useful for:
Behavior modification research
diagnosing teaching and learning problems
studying classroom management methods
development of students’ skill
studying a problem in detail
A form of action research
Experimental control
It is a quantitative design.
multiple, reliable observations of student behavior
can be observation, questionnaire, test
can not have pre-test effect
must be able to give it frequently
must be reliable
Detailed description of the treatment
replication of the treatment effects
I do single-subject studies all of the time in my classroom. It might not be a “formal” study, but I am observing reactions to what I do and what is expected in my classroom. Often I base what I do off of what worked in the past.
Reliable observations of behaviors
Operational definition of to-be-observed (target) behaviors
Careful training of observers
Frequent checks of observer reliability
Control of observer bias
SINGLE-SUBJECT RESEARCH DESIGNS
AB designs
Basic to all single-subject research is “A-B” logic: (1 Problem – low internal validity)
Condition A: environmental conditions are constant, target behavior is observed to occur at consistent, stable rate
Condition B: one of the environmental conditions changes, corresponding changes in the target behavior observed
A-B-A design
B-A-B design
A-B-C-B design
Multiple Baseline Designs
are used when: you cannot withdraw or reverse a treatment, or you cannot demonstrate a treatment effect with an A-B-A design
Summary: 2 Basic Designs
ABA and Multiple Base
Both based on the concept of multiple measures across time and the AB sequence of treatment
Require: reliable frequent measurement, clear specification of observation, and inter-rater reliability
