Biomedical Engineering Reference
In-Depth Information
In this section, we have shown that formative evaluation
can be conducted within the framework of experimental
design, and evaluative fi ndings can at the same time be
provided to the manager of the training program that is
being evaluated, via the study monitoring committee or
another appropriate channel. This means that the full range
of evaluative approaches is available to the formative
evaluator, including not only quasi-experimental designs but
experimental designs (i.e., RCT) as well.
12.5 The good news, part 2
The preceding material incorporated an existence proof,
showing that under specifi ed conditions, training program
modifi cation could take place in response to evaluative
fi ndings developed within an experimental design. The
following questions can still be raised: What are the
implications of this for evaluation practice? Does anyone
care? The answer to these questions is yes.
Let us look at a methodologically analogous situation,
that of clinical trials of investigational new drugs. There is a
long history of interest in adaptive designs in clinical trials,
dating from Abraham Wald's pioneering research in the
1940s.
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The FDA has expressed interest in adaptive clinical
trials and the associated research designs. The dilemma of
clinical trials has been described well by Lowe:
In too many cases, the chief result of a trial is to show
that the trial itself was set up wrong, in ways that only
became clear after the data were unblinded. Did the
numbers show that your dosage was suboptimal
partway into a two-year trial? Too bad - you probably
weren't allowed to know that. Were several arms of
