The NICE glossary provides brief definitions and explanations of terms used on the website. The terms describe how NICE works and how its guidance is produced.

Our glossary excludes specific clinical and medical terms. If you cannot find the term you are looking for, please email us so that we can consider adding it to the glossary.

Some definitions and examples are based on those in the HTAi consumer and patient glossary, with thanks to Health Technology Assessment International.

For terms used in social care, the Care and Support Jargon Buster from Think Local Act Personal is a useful guide to the most commonly used social care words and phrases, and what they mean.

  • Hazard ratio

    The hazard or chance of an event occurring in the treatment arm of a study as a ratio of the chance of an event occurring in the control arm over time.

  • Health economics

    Study or analysis of the cost of using and distributing healthcare resources.
  • Health gain

    A measured improvement in the health of a person or a population.
  • Health impact assessment

    A combination of procedures, methods and tools used to judge a policy, programme or project. For example, a health impact assessment could be used to determine how a proposal for a new road or new airport runway will affect local people's health. The process involves: gathering information on the areas and communities affected and using various tools to predict how it will impact on health; evaluating the options; and making recommendations to ensure any potential harm is minimised or opportunities to improve health are maximised. Other similar procedures include strategic environmental assessment, sustainability appraisal and environmental impact assessment.
  • Health inequalities

    The gap in health status and in access to health services between different groups, for example, those with different socioeconomic status or different ethnicity, or populations in different geographical areas. More information on health inequalities can be found on the Department of Health website. See also Health inequities.

  • Health inequities

    A health inequity is an unnecessary, avoidable, unfair and unjust difference between the health or healthcare of one person, and that of another. 'Health inequity' should not be used interchangeably with the term 'health inequality' because the differences in health or healthcare that people experience are not necessarily unfair or unjust. Health inequity is concerned with social justice, values or politics, while inequalities in health are a matter of fact. Addressing them can have considerable political implications because of the value judgement involved: not all people will judge the same health difference to be unfair.

  • Health needs assessment

    A systematic process used by NHS organisations and local authorities to assess the health problems facing a population. This includes determining whether certain groups appear more prone to illness than others and pinpointing any inequalities in terms of service provision. It results in an agreed list of priorities to improve healthcare in a particular area.
  • Health promotion

    Giving people the information or resources they need to improve their health. As well as improving people's skills and capabilities, it can also involve changing the social and environmental conditions and systems that affect health.
  • Health Research Authority

    This organisation protects the rights of patients, including by regulating the use of data collected within health and social care for research and product development.

  • Health status

    How healthy a person, group, or population is. This could be assessed by the person or group concerned or by using more objective measures. The judgement is usually based on the person's ability to carry out everyday activities and how free they are from pain.
  • Health technology

    Drugs, medical devices (such as artificial hip joints), diagnostic techniques, surgical procedures and other treatments to improve health or prevent ill health.
  • Health technology assessment

    Independent research about the effectiveness, costs and broader impact of healthcare (treatments and tests) for those who plan, provide or have care in the NHS.

  • Health technology evaluations

    Products assessed using the early value assessment approach are published as health technology evaluations.

  • Heterogeneity

    A term used in meta-analyses and systematic reviews to describe when the results of a test or treatment (or estimates of its effect) differ significantly in different studies. Such differences may occur as a result of differences in the populations studied, the outcome measures used or because of different definitions of the variables involved. It is the opposite of homogeneity.

  • Hierarchy of evidence

    Study types organised in order of priority, based on the reliability (or lack of potential bias) of the conclusions that can be drawn from each type.

  • Highly specialised technologies guidance

    NICE guidance on the use of new and existing highly specialised medicines and treatments within the NHS in England.

  • Highly Specialised Technologies Programme

    Makes recommendations on the clinical and cost effectiveness of new and existing highly specialised medicines and treatments. It only considers drugs for very rare conditions.

  • Homogeneity

    A term used in meta-analyses and systematic reviews to indicate that the results of studies are similar; the opposite of heterogeneity. Study results are also regarded as homogeneous if any differences could have occurred by chance.