Sometimes the simplest of ideas are the most important. However, sometimes they can be deceptively simple. Study registration is one of those.

Health-related research doesn’t just happen in one country, in one institution. It happens where it matters, where it needs to happen, where the experts are, where patients and the public are. It is a collective endeavor where wonderful things emerge from a complicated and sometimes complex web of different ideas, funders, research institutes, and people. Wonderful though that is, it does present us with a problem: how do we know what has been done and who is doing what in such a global and messy system? Study registration is part of the answer.

Why is study registration important?

At its heart is a simple idea: that all studies should be registered in publicly accessible places. The reasons for this span ethical, moral, accountability, research integrity and waste reduction perspectives.

For example:

• Openness is important for the research community (funders, academics, publishers, regulators etc) to be held to account and for patients and the public to know what research has happened and what is going on.

In summary the general consensus is that registries like ISRCTN are a good, necessary, and valuable part of our global research system.

• The revised Declaration of Helsinki, widely regarded as the cornerstone document on human research ethics, states “every clinical trial must be registered in a public accessible database before recruitment of the first subject”.
• The World Health Organization (WHO), a significant player in advancing the principles and practice of clinical trial registration, states that “the mission of the WHO International Clinical Trials Registry Platform is to ensure that a complete view of research is accessible to all those involved in health care decision making. This will improve research transparency and will ultimately strengthen the validity and value of the scientific evidence base”.
• The International Committee of Medical Journal Editors advocates for trial registration and many journals now will not consider publishing trials unless they are appropriately registered.
• The NIHR and many other research funders insist on registration for trials and evidence synthesis and fund registries like ISRCTN for trials and PROSPERO for systematic reviews.
• The UK’s Health Research Authority has made registration mandatory for ethics approval for clinical trials. In other words you can’t do a clinical trial without it.
• The Ensuring Value in Research (EViR) global funders’ forum devotes one of its ten guiding principles to study registration. The forum says “Studies should be registered in an appropriate, design-relevant publicly accessible registry at study inception whenever possible” and that “registration is important to prevent unintentional duplication and provide an audit point for later accountability (e.g. to identify non-publication)”.
• Registration is a requirement of US Food and Drug Administration approval and it features in the European Union Clinical Trials Directive.

I could go on. In summary though the general consensus is that registries like ISRCTN are a good, necessary, and valuable part of our global research system. We should be rightly proud of our community in health-related research that we have registries and see the importance of them.

So, job done. All studies are registered, are they? Well no, it’s not that simple, not even for clinical trials and certainly not for other study types.

Challenges to achieving registration of all studies

There are a number of challenges. Firstly, some researchers hesitate due to fears of plagiarism of intellectual property or loss of commercial advantage. Secondly, to do it well takes time, care and thoughtfulness. Many do precisely that – unfortunately many do not. Even if done right at the beginning, it takes commitment to keep entries up to date (as discussed in a previous blog).

Foreheads will hit keyboards, mine included, if we find ourselves needing meta-meta-registries!

It’s also not always clear where to register. Sometimes it is fairly straightforward, for example for clinical trials (e.g. ISRCTN) and evidence synthesis (e.g. PROSPERO),  and there are new capabilities coming online, for example for preclinical research (e.g. https://www.preclinicaltrials.eu/). But what about other types of research? Where should they register? That might not be clear, but what is clear is that it would be counterproductive for the solution to be an explosion of siloed registries all focused on niche areas.

An obvious solution would be the introduction of so-called meta-registries: registries of registries that provide single points of access to a large number of primary registries. That sounds interesting but needs doing with care. To do well, minimum datasets need to be agreed across the registries and we would have to watch out for the proliferation of meta-registries. Foreheads will hit keyboards, mine included, if we find ourselves needing meta-meta-registries!

What next?

So where do we go next with study registration? While the case has been made for clinical trial registration, we need to make it much easier to comply with requirements and to monitor non-compliance. Beyond clinical trials more work is needed – the case needs making more strongly and the infrastructure, for example where to register other study types, needs working on.

Whilst this might be difficult to achieve, we shouldn’t lose sight of the fact that at its heart study registration is a simple idea, but one that has already had a major impact on the quality, integrity and value of clinical trials and has the potential to do so more broadly for health-related research.

The views and opinions expressed in this blog are those of the authors and do not necessarily reflect those of the NIHR, NHS or the Department of Health and Social Care.