Background: The scientific process in medicine is complicated. Obtaining high-quality data to guide management requires hypothesis formulation, data to support the hypothesis and study replication. Time and again beneficial findings in therapeutic studies fail to be replicated in subsequent studies. A single positive trial may cause some to feel it unethical to assign patients to a standard therapy that could potentially deprive them of benefit. Alternatively, pharmaceutical companies have little impetus to attempt or support collecting additional data that may jeopardize their product. In research, repetition is the pillar on which clinical trials results should be founded on. As this may not be feasible, complete transparency of all aspects of a trial are essential.
One of the most hotly debated topics in emergency medicine is the use of systemic thrombolysis in acute ischemic stroke. There are only two randomized clinical trials that demonstrate benefit in neurologic outcomes: NINDS-II and ECASS-III (see table below). Methodological experts, however, have raised concerns that both studies had baseline imbalances in stroke severity that may have biased the trials final results. Both studies have undergone re-analysis taking these baseline differences into account.