Chapter 14.4, Problem 8LO

Identify the strengths and weaknesses of a multiple-baseline design and describe the circumstances in which it should or should not be used.

To determine

The strengths and weaknesses of a multiple baseline design and understand the circumstances where it can be used and where it cannot be used

Answer to Problem 8LO

Solution:

Definition of multiple baseline design: In this design multiple persons or aspects are measured both before and after the treatment. The treatments in this design start off at different times. Data is gathered from different subjects, after application of the treatment at different times and inference about the relation is drawn from the same.

Explanation of Solution

Strengths of multiple baseline designs:

1. This design allows eliminating the effect of other variables that may influence the relation under study
2. The concept of applying treatment at different time allows the researcher flexibility to the research design
3. By applying the treatment at different times, and making same observation in all of them, assures the conclusion more loudly
4. It provides better internal validity about the observation, since different subjects at different time and situation provide the same outcome
5. This design also strengthens the external validity since it allows to generalize the result so obtained by the multiple baseline design
6. This design is easy to apply and conceptualize.

Weaknesses of multiple baseline designs:

1. There are certain functional relations that may not be clearly understood by this design
2. This design is time consuming and requires lot of resources at different locations and time.
3. There are chances of covariance occur in such research designs

Circumstances when this design is used:

1. It is used in the situation when reversal of the treatment is considered to be unethical
2. When practically it is productive to incorporate multiple subjects, this design is ideal
3. In situations where withdrawal of the treatment fails to remove the effect of treatment, the reversal design does not work, then the multiple baseline designs help to research such a subject.

Circumstances when this design should not be used:

1. It is obvious not to use this design when the subjects behave differently
2. If the research deals with one subject on a particular setting observing one particular trait, like some specific kind of illness, in that situation this design cannot be implemented
3. There are experiments where more than one intervention is needed. In that case multiple baseline design may not be useful
4. When there is deficiency of resources to monitor the multiple subjects at different locations this design may be difficult to be implemented.

Conclusion:

Thus we conclude that multiple baseline design is used when there are more subjects, resources and time available to implement this design efficiently. It must be used when the relation between the variables is not functional. This design provides better demonstration of cause-effect relation.