2. Why Access To Clinical Trial Results Is Important?
The concept of evidence-based medicine
(EBM) was created in the early 1980s as clinical practice
became more data-driven and literature based. EBM is now an essential part of what is taught at medical school. Information on treatment efficacy
is important for making informed treatment decisions by the patients and their physicians.
It is important not to limit the search for evidence about a treatment to a single publication. When comparing results coming from different sources, it is important to keep in mind the different levels of evidence. The hierarchy of evidence relates to the strength of the trial design and statistics
deployed and not necessarily to the clinical significance
. Randomised, controlled, blinded trials provide the best scientific evidence of benefit
but sometimes are not available. Meta-analysis
can be flawed because of publication bias
In general, the hierarchy of trials for obtaining evidence is:
powered, randomised controlled trial, or meta-analysis of
randomised trials showing statistically consistent results.
trials inadequately powered, possibly biased, or showing statistically
trials with concurrent controls.
trials with historical controls (i.e. typical single arm Phase II trial).
committee review, case reports, retrospective trials.
Patients can learn about clinical trial
from their doctor and also by accessing the published information
directly. Access to clinical trial
results for researchers is paramount for improving
by reducing the duplication or replication of research efforts.