Why should statistical methods work for intervention trials involving volunteers?
Intervention trials are typically analyzed by using the same statistical methods for the analyzing random samples. Almost all intervention trials involve volunteers, usually recruited locally. If convenience samples are inappropriate for surveys, how can they be appropriate for intervention trials? There are two distinct issues to address–validity and generalizability. • Validity is concerned with whether the experiment is valid, that is, whether observed differences in this group indicate a real difference in treatments insofar as these subjects are concerned. • Generalizability is concerned with whether the results can be generalized to any other group of individuals. The reason volunteers can be used to make valid comparisons comes from the use of randomization in the assignment of treatments. It is beyond the scope of these notes to give mathematical proofs, but the common statistical methods that are appropriate to compare simple random samples are also valid for deciding whether
Related Questions
- Does the application have to have full background, methods, statistical analysis plans, etc. for each phase of the Intervention Development plan?
- Why should statistical methods work for intervention trials involving volunteers?
- How is RTI different from other methods of special education intervention?
