In an attempt to make the data of clinical trials approved by the ethics review board of the World Health Organization (WHO) easily accessible to the scientists across the world, WHO in association with Current Controlled Trials (CCT) have decided to distinguish all such trials by using a unique numbering system.

Hereafter, all randomized controlled trials approved by the WHO ethics review board will be assigned an International Standard Randomised Controlled Trial Number (ISRCTN) thereby helping the scientific community to keep up-to-date with current research.

Scientific community in developing countries like India is known to benefit most from ISRCTN as it would lead to knowledge sharing, access and utilization of medical knowledge generated in low and middle income countries.

ISRCTN is a unique number that provides a means of identifying and unambiguously tracking a trial throughout its life cycle. Information about trials, that have received this number, can be obtained from an online register maintained by Current Controlled Trials. Access to this Register is free of charge.

Randomised controlled trials are considered the best way to compare - in an unbiased manner - the effects of particular interventions on people or populations either for health promotion, prevention, treatment or for rehabilitation. They are one of the main sources of medical knowledge, yet information about these trials is difficult to find. This is because several trials may have the same title, one trial may be reported in several places under different titles, and many trials are never reported at all, stated a WHO release.

Information is even more difficult to find about neglected diseases that disproportionately affect poor and marginalized populations. WHO supports and funds much of the research in this area. However so far, there has been no mechanism to make the information generated from this research easily available to researchers, particularly those in developing countries whom it affects most. By providing free access on the internet, ISRCTNs offer a way to keep the international community informed about these clinical trials.

In the first phase, all trials included in the HRP/UNDP/UNFPA/WHO/ World Bank Special Programme of Research, Development and Research Training in Human Reproduction trials register have now been included in the ISRCTN Register. "Our trials register has been operational for two years and we welcome this opportunity to make our research programme in sexual and reproductive health more accessible to the wider community," says Dr Paul Van Look, Director of Reproductive Health and Research at WHO.

Randomised trials in the other major research areas that the WHO supports - infectious diseases, childhood diseases, vaccines and others will be added shortly to the ISRCTN Register.

The ISRCTN Register also tackles the problem of publication bias - trials that are not published either because of negative findings, or language barriers, or inaccessibility of the researcher to journals. By registering clinical trials at the start of the research, the ISRCTN Register will ensure that this information is now more easily available.

"Although trial registration is an important step on its own, it should not be seen as an end in itself," says Dr. Timothy Evans, assistant director-general of the Evidence and Information for Policy cluster of the WHO. "Only when these registers are efficiently used can they serve the purpose they are set up for. As an international agency with a mandate to set standards and norms, WHO will take steps to encourage its Member States to support the publication of research conducted within their countries and encourage the use of such registers."

Working across 192 countries, one of the major challenges for WHO is coordinating national research activity in the global effort to reduce maternal mortality and stem pandemics like HIV, re-emergence of tuberculosis and malaria, and eradication of polio.

"We are delighted that the WHO are taking a lead in the registration of trials with an ISRCTN," says CCT's managing director Anne Greenwood. "The ISRCTN scheme was conceived to address the confusion experienced by the research community. For controlled trials to be useful on a global scale, it is critical that research be coordinated. ISRCTNs offer a way to do exactly that."

The ISRCTN Register represents the first online service that provides unique numbers to randomised controlled trials in all areas of health care and from all countries around the world. Access to the ISRCTN Register is completely free and open to the public. Since its launch in May 2003, the Register has assigned ISRCTNs to over 1800 trials, and is growing fast.

The ISRCTN Register has been developed by Current Controlled Trials Ltd, part of the Current Science Group of companies. The Group has its headquarters in London, UK and also has offices in Philadelphia and Tokyo.