1. Single- Subject Research Designs
Chapter 14

2. Single- subject designs
Single- subject designs, or single- case designs, are research designs that use the results from a single participant or subject to establish the existence of cause- and- effect relationships.

3. Phases and phase changes
A phase is a series of observations of the same individual under the same conditions. When no treatment is being administered, the observations are called baseline observations.

4. Visual Inspection Techniques
Unfortunately, there are no absolute, objective standards for determining how much of a change in pattern is sufficient to provide a convincing demonstration of a treatment effect.
The most convincing results occur when the change in pattern is immediate and large.

5. 4 types of change Change in average level Immediate change in level
Change in trend
Latency of change.

6. Change in average level
Change in trend
Immediate change in level
Latency in Change

7. The problem with single subject design

9. THE ABAB REVERSAL DESIGN
the majority of single- subject research studies use ABAB design;
consists of four phases: a baseline phase ( A), followed by treatment ( B), then a return to baseline ( A), and finally a repetition of the treatment phase ( B).

10. Effective
A= no treatment

11. Not Effective

12. Variations on the ABAB Design

13. 1- B&B1 not working use C

14. 2- B not working add C
B= Graduated exposure
C= Reinforcement

15. 3- MULTIPLE- BASELINE DESIGNS
1- Eliminates the need for a return to baseline and therefore, 2- Is particularly well suited for evaluating treatments with long- lasting or permanent effects.

16. 3- MULTIPLE- BASELINE DESIGNS
Examples
A therapist uses the same method for 2 different behaviors (across behaviors)
For one behavior that is exhibited in 2 different situations. (across situations)
A teacher uses the same method on 2 different individuals (across subjects)

17. Person1
Person2
2 different students

18. Yelling
Crying
2 different behaviors

19. School
Home
2 different situations.

20. Weaknesses of the Multiple- Baseline Design?
a treatment applied to one behavior may generalize and produce changes in the second behavior.
one behavior may show a large and immediate change, but the second behavior may show only a minor or gradual change when the treatment is introduced
one INDIVIDUAL may show a large and immediate change, but the second behavior may show only a minor or gradual change when the treatment is introduced

21. 4- Dismantling design
A dismantling design, also called a component- analysis design, consists of a series of phases in which each phase adds or subtracts one component of a complex treatment to determine how each component contributes to the overall treatment effectiveness.

22. Example

23. 5- The Changing- Criterion Design
The criterion level is changed from one phase to the next.

24. Smoking Treatment

25. 6-The Alternating- Treatments Design
In an alternating- treatments design, also called a discrete-trials design, two ( or more) treatment conditions are randomly alternated from one observation to the next.

26. Example - Alternate weeks

27. Group Discussion
Suppose you are interested in performing an observational study of kindness (kind behavior) among students in a school. Describe one method to quantify this behavior: that is, explain how you could convert the observations into numerical scores.
In most research studies, statistical techniques are used to rule out chance as a plausible explanation for the results. In single-subject research, how is chance (or coincidence) ruled out as a plausible explanation for the observed treatment effects?​