Biomedical Engineering Reference
In-Depth Information
developers to evaluative fi ndings is clear; they will consider
making program improvements based on the evaluative
fi ndings. What about the response of management?
12.2 Feedback versus
research design
The question often arises in the formative evaluation of a
training program or other program: what is the effect of the
dissemination of evaluative fi ndings during the life of the
program? It is often assumed that the “experimental design”
dictates that intervention (e.g., training materials, training
“script,” etc.) must remain invariant during the program
cycle. Friedman, Furberg, and DeMets
4
state that a clinical
trial study protocol:
should be developed before the beginning of subject
enrollment and should remain essentially unchanged
except perhaps for minor updates. Careful thought and
justifi cation should go into any changes. Major revisions
which alter the direction of the trial should be rare.
If preliminary fi ndings were fed back, this would allow a
modifi cation of the training materials and other aspects of
the program, thus invalidating design and the evaluative
research fi ndings.
This position has until recently been held regarding clinical
trials in the pharmaceutical industry. As Derek Lowe
5
has
expressed it, in a clinical trial:
establish your “null hypothesis” (typically that your
drug is no better than a placebo or the current standard
