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  • ABPI

    Association of the British Pharmaceutical Industry: a trade association for UK pharmaceutical companies.
  • Abstract

    A brief summary of the study and its results. It should tell you what the study tried to show, how the researchers went about it, and what they found.
  • AcoRD

    ‘Attributing the costs of health and social care Research and Development’. A DHSC framework to identify, attribute and recover the various costs associated with research in the NHS. For more information see: AcoRD guidance.
  • Action research

    Action research is used to bring about improvement or practical change. A group of people who know about a problem work together to develop an idea about how it might be resolved. They then go and test this idea. The people who take part in the testing provide feedback on their experiences. They may also identify further actions that need to be researched and tested. This cycle of developing solutions and testing them is repeated until the problem has been solved.
  • Adverse drug reaction

    An unwanted or harmful reaction which occurs after administration of a drug or drugs and is suspected or known to be due to the drug(s).
  • Adverse event

    An unfavourable outcome that occurs during or after the use of a drug or other intervention, but is not necessarily caused by it.
  • Adverse reaction

    Any untoward and unintended response to an investigational medicinal product related to any dose administered.
  • Advisory group

    Many research projects have an advisory group (or steering group). The group helps to develop, support, advise and monitor the project. The group often includes people who use services, carers, researchers and other health and social care professionals, who can provide relevant advice.
  • Allied Health Professionals

    Allied health professionals (AHPs) are people who work in health care professions distinct from dentistry, nursing, medicine, and pharmacy. They provide a range of diagnostic, technical, therapeutic, and support services in connection with health care, for example, occupational therapists, dietitians and podiatrists.
  • AMRC

    Association of Medical Research Charities: a membership organisation of the leading medical and health research charities in the UK.
  • AMS

    Academy of Medical Sciences: the independent body in the UK representing the whole spectrum of medical science.
  • Applied Research Collaborations

    NIHR Applied Research Collaborations (ARCs), support high quality, generalisable, applied health and care research that responds to, and meets, the needs of local populations and local health and care systems.
  • ARCs

    NIHR Applied Research Collaborations (ARCs) support high quality, generalisable, applied health and care research that responds to, and meets, the needs of local populations and local health and care systems. The collaborations also support, facilitate and increase the rate at which research findings are implemented into practice.
  • Arm

    Refers to a group of participants allocated to a particular treatment. In a randomised controlled trial, allocation to different arms is determined by the randomisation procedure. Many controlled trials have two arms, a group of participants assigned to an experimental intervention (sometimes called the treatment arm) and a group of participants assigned to a control (the control arm). Trials may have more than two arms.
  • Article Processing Charge

    (APC) A publishing fee paid to journals to publish a research article open access.
  • Attrition

    The loss of participants during the course of a study. Also called 'loss to follow up'.
  • Audit

    An audit of health or social care involves carrying out a systematic assessment of how well that care is being delivered. Current policy and practice is compared with an agreed standard, so that any problem areas can be identified and improved. Later, the audit can be carried out again to check that the changes made have actually made a difference
  • Author Accepted Manuscript

    (AAM) The author’s version of a research article that has been peer-reviewed and is accepted for publication, prior to typesetting by the publisher. It may otherwise be known as the ‘author manuscript’ or ‘final author version’ or ‘post-print’.