Rationale, aims and objectives
New therapies are increasingly approved by regulatory agencies such as
the Food and Drug Administration (FDA) and the European Medicines Agency
(EMA) based on testing in non-randomized clinical trials. These
treatments have typically displayed “dramatic effects” (i.e., effects
that are considered large enough to obviate the combined effects of bias
and random error). The agencies, however, have not identified how large
these effects should be to avoid the need for further testing in
randomized controlled trials (RCTs). We investigated the effect size
that would circumvent the need for further RCTs testing by the
regulatory agencies. We hypothesized that the approval of therapeutic
interventions by regulators is based on heuristic decision-making whose
accuracy can be best characterized by the application of signal
detection theory (SDT).