Science is critical for improving the effectiveness of addiction treatment

Part 1 of the Independent Review of Drugs, published in 2020, highlighted the increasing severity of the UK’s drug problem and its run-down treatment and rehabilitation services. [1] Part 2 of the review is released today and recommends new funding and new accountability systems to rebuild addiction treatment and recovery services across England and Wales. [2] This plan is more likely to succeed if the UK’s under-nourished addiction science receives proper attention and resources.

Covid-19 has taught us that our response to public health crises is best when guided by good science. Popular opinion and political reality are important, but will help develop effective health policy only when informed by the best available scientific evidence. [3,4] Scientifically uninformed choices can increase sickness and deaths. The same applies to treatments for addictions and the commissioning thereof. 

Opinions regarding drug treatment are often strongly held. This is a reason for more, not less, rigorous scientific inquiry. The government needs the best independent research to guide instructions for commissioners and practitioners. Touters of miracle solutions attract media interest, but the rhetoric must be challenged and subjected to objective study. 

What research should be done? How should its focus and methods be decided? Objectivity and equipoise are crucial to the selection and monitoring of new research activity. Such activity can draw on existing advice and systems available through the National Institute for Health and Care Excellence (NICE), Cochrane reviews, and other overviews. [5-11] Their contributions will improve the ability of government, commissioners, and practitioners to plan responses that have a greater impact. Future strategic decision making can then be informed by findings from purposely selected research studies, alongside methodologically rigorous systematic reviews.  

England and Wales do not have a focused or ringfenced system of addiction[s] research funding, unlike other countries (the USA, Canada, Australia). Centrally commissioned research mostly investigates initiatives selected by politicians, without sufficient input from public health experts, frontline clinicians, or addiction scientists. 

A strong, sustainable, independent research capacity is required, albeit with a solid link to policymakers, to identify key questions that are critical for policy and practice. Scientists must then identify the strongest study designs relevant to the specific questions. Research methods will include randomized controlled trials, cluster trials, stepped wedge trials, time series studies, prospective cohort studies, etc, as well as event driven studies of the impact of changes in policy and practice. Substance misuse problems often straddle social and crime dimensions as well as health, but sound scientific methods can still be applied. [12,13]

People’s lived experiences of addiction and recovery also require scholarly attention. Addiction is a highly variable experience across individuals, and so too can be the processes of recovery. Non-trial research methods (including cohort studies and qualitative studies) will be needed to obtain findings not accessible through research methods traditionally considered stronger, although attention to research rigour will remain vital.  

The existing system for commissioning relevant research is not good enough. Despite a growing problem and continuing political and public concern, few high quality trials of addiction treatments have been conducted in the UK. A new national system for addiction[s] research is required (akin to the US National Institute on Drug Abuse, NIDA) specifically to investigate areas of critical challenge where research can identify strategies to create greater public good. Through NIDA funded research, we now have a much better understanding of the processes of addiction, effective treatments, and pathways of recovery. With the NHS providing free universal healthcare at the time of need, a UK based central research initiative would be well placed to engage with nationally important questions about policy and practice (better placed than its North American equivalents). [14] The areas for specific research will need to be identified through dialogue between scientists and those steering policy and practice; they will change as the field develops. This will require guidance from or adoption by existing grant awarding bodies (such as the UK’s National Institute for Health Research, NIHR) and will be most efficient if  undertaken collaboratively by appointment, co-option, or secondment of high calibre addiction scientists. A ringfenced budget will be needed initially, specifically for research that is relevant to policy and practice, which might otherwise not attract sufficient public or scientific interest, even though it is vital for making decisions regarding policy and practice.

Conducting and publishing more and better research, and nurturing the next generation of addiction researchers are also vital. A dedicated research training pathway would establish critical mass and a peer group of addictions research trainees, as in other countries, such as the USA, where training fellowships support the development of research skills relevant to policy and practice. Research training pathways should be established for clinical addiction scientists as well as non-clinical addiction scientists. 

The success of such an approach will be twofold. First, it will help unravel basic science questions about the nature of addiction. Second, it will support an evidence-informed national strategy for commissioning, providing, and delivering drug treatment and recovery services, generating gains in public health and community safety that can be shared widely. [15]

John Strang, National Addiction Centre, Institute of Psychiatry, Psychology and Neuroscience (IoPPN), King’s College London.

Keith Humphreys, U.S. Veterans Affairs and Stanford University Medical Centers.

Carol M Black, Chair of the Centre for Ageing Better; Chair of the NHSE/I Health and Wellbeing Advisory Board, UK.

Competing interests: Carol Black led the Independent Review of Drugs. Keith Humphreys served without compensation on the core analysis and writing team. John Strang provided expert scientific consultation. JS has worked with treatment providers in the statutory and voluntary sectors and has conducted clinical and wider research with various funders, including industry, to develop new treatments (but does not receive any personal income from this): see ; JS is an NIHR senior investigator, and his research is supported by the National Institute for Health Research (NIHR) Biomedical Research Centre for Mental Health at South London and Maudsley NHS Foundation Trust and King’s College London. KH holds grants from the U.S. National Institute on Drug Abuse and Veterans Health Administration. 


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