1. Single-Subject Research

2. Advantages of Single-Subject Research Methods
Useful for:
behavior modification research
diagnosing teaching and learning problems
studying classroom management methods
development of students’ skills

3. Advantages of Single-Subject Research Methods (2)
Useful for:
training studies with special needs students
studying a problem in great detail
functioning simultaneously as teacher and researcher (action research)

4. PROCEDURES USED TO ACHIEVE EXPERIMENTAL CONTROL IN SINGLE SUBJECT RESEARCH DESIGNS
Multiple, reliable observations of student behavior
Detailed description of the treatment (IV)
Replication of the treatment effects (across subjects, settings, and/or behaviors)

5. Procedures for obtaining 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

6. Single-Subject Research Designs

7. Basic to all single-subject research is “A-B” logic:
Condition A: environmental conditions are constant; target behavior is observed to occur at consistent, stable rate.
Condition B: one of the environmental conditions changes and there is a corresponding change observed in the target behavior.

8. Logical inference: The change in environmental conditions had something to do with the observed change in behavior; if we can assume that the behavior would have remained at its stable rate as long as Condition A remained in effect. Change in environment: the “treatment”

9. Research Designs A-B design A-B-A design Multiple baseline designs:
A-B-A-B design
B-A-B design
A-B-C-B design
(“C” is a 2nd, different treatment.)

11. Problems with the A-B design:
Low in internal validity
Cannot attribute observed changes in the target behavior to the treatment
Other factors may be responsible for observed changes in behavior
Use only when no suitable alternative is available (or for pilot study)

13. Problems with A-B-A design
Sometimes behaviors that are “treated” during the treatment phase (B) do not return to baseline because the behaviors cannot be “unlearned” or reversed.
Therefore, it is difficult to show that the treatment has, in fact, brought about the observed change in behavior.

14. A Multiple Baseline Design
Behavior:
X 0 X 0 X 0 X 0 0
X 0 X 0 X
X 0

15. Multiple Baseline Designs
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

17. MBD across behaviors
(1) Take baseline measure on two or more behaviors of one student.
(2) Treatment is applied to Behavior A after baseline stabilizes.
(3) After observed change in Behavior A occurs, treatment is applied to Behavior B.

18. MBD across situations
(1) one behavior of one student is observed across two or more situations (e.g., classroom, playground);
(2) after baseline rates stabilize in setting 1, treatment is applied;
(3) after behavior changes in setting 1, treatment is then applied in setting 2.

19. MBD across individuals
(1) a problem behavior of two students is targeted for treatment
(2) after baseline rate of the behavior of student A stabilizes, the treatment is applied to Student A;
3.) after Student A behavior is observed to change, the treatment is then applied to Student B.

20. Various combinations of these MBDs can be used:
MBD across behaviors and situations
MBD across behaviors and individuals
MBD across situations and individuals
MBD across behaviors, situations, and individuals

21. Sometimes, multiple, and different treatments can be used in the same single-subject design.

23. Sometimes, single-subject research begins with the treatment phase, followed by a baseline phase, and then a second treatment phase (B-A-B) design

28. “Teaching multiplication facts to students with learning disabilities”
Wood, Frank, & Wacker (1998).
“Teaching multiplication facts to students with learning disabilities”

29. Single subject study...
Example of multiple-baseline across subjects and across behaviors research.
Allowed investigators to determine if
simple practice increases student learning
instruction generalizes to other multiplic. facts
Purposes: (1) improve students’ multiplication skills; (2) evaluate efficacy of instructional program.

30. Students taught four skills:
Ask selves a question about multiplication problem;
problem-solving strategy;
mnemonic strategy (key-word method);
attribution of success to correct use of strategies.

31. Visual analysis vs. Statistical analysis