Clinical trials are experiments or observations done in clinical research. Such prospective biomedical or behavioral research studies on human participants are designed to answer specific questions about biomedical or behavioral interventions, including new treatments (such as novel vaccines, drugs, dietary choices, dietary supplements, and medical devices) and known interventions that warrant further study and comparison. Clinical trials generate data on safety and efficacy.
They are conducted only after they have received health authority/ethics committee approval in the country where approval of the therapy is sought. These authorities are responsible for vetting the risk/benefit ratio of the trial – their approval does not mean that the therapy is 'safe' or effective, only that the trial may be conducted.
Clinical trials are substantial financial investments for their sponsors and substantial time investments for participating clinicians and patients. Trials, when done well, can change the standard of care, offering new hope for some diseases or improved understanding for others. Yet there are persistent concerns that the results of many trials languish, unpublished and unreported, preventing the scientific community from acting on important clinical data 1).
Publication of clinical trials, especially those with negative results, remains vital, helping to improve future trials, steering resources away from fruitless therapies, and informing patients about better clinical approaches. Publication bias has its roots in both the trialists who write papers—or neglect to—and the journals that reject them. Encouragingly, there are some indications that publication bias has improved at the journal level, with more negative trials getting to press 2) 3).