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National Collaborating Centre for Chronic Conditions (UK). Stroke: National Clinical Guideline for Diagnosis and Initial Management of Acute Stroke and Transient Ischaemic Attack (TIA). London: Royal College of Physicians (UK); 2008. (NICE Clinical Guidelines, No. 68.)

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Stroke: National Clinical Guideline for Diagnosis and Initial Management of Acute Stroke and Transient Ischaemic Attack (TIA).

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4Glossary and definitions


Prognostic score to identify people at high risk of stroke after a TIA. It is calculated based on:


– age (≥60 years, 1 point)


– blood pressure at presentation (≥140/90 mmHg, 1 point)


– clinical features (unilateral weakness, 2 points or speech disturbance without weakness, 1 point)


– duration of symptoms (≥60 minutes, 2 points or 10–59 minutes, 1 point).

The calculation of ABCD2 also includes the presence of diabetes (1 point). Total scores range from 0 (low risk) to 7 (high risk).


A drug used for thrombolysis.


A group of drugs used to reduce the risk of clots forming by thinning the blood.

Antiphospholipid syndrome

Sometimes called ‘sticky blood syndrome’ because the blood clots too quickly due to antibodies that form against the body’s phospholipids.


A group of drugs used to prevent the formation of clots by stopping platelets in the blood sticking together.

Arterial dissection

This is caused as a result of a small tear forming in the tunica intima lining of the arterial wall.

Barthel Index

Scale measuring daily functioning specifically relating to the activities of daily living or mobility. Scores range from 0 to 100.

Bedside swallowing assessment

A term covering a range of techniques.


Body mass index – an index of body weight corrected for height.

Case series

Report of a number of cases of a given disease, usually covering the course of the disease and the response to treatment. There is no comparison (control) group of patients.

Carotid artery

Main arteries in the neck supplying oxygenated blood to the brain.

Carotid endarterectomy (CEA)

A surgical procedure used to clear the inside of the carotid artery of atheroma.

Carotid stenosis

The narrowing of the carotid arteries in the neck.

Case-control study

Comparative observational study in which the investigator selects individuals who have experienced an event (for example, developed a disease) and others who have not (controls), and then collects data to determine previous exposure to a possible cause.

Cohort study

A retrospective or prospective follow-up study. Groups of individuals to be followed up are defined on the basis of presence or absence of exposure to a suspected risk factor or intervention. A cohort study can be comparative, in which case two or more groups are selected on the basis of differences in their exposure to the agent of interest.

Confidence interval (CI)

The probability of the observed data (or data showing a departure more extreme from the null hypothesis) when the null hypothesis is accepted.

Cochrane review

The Cochrane Library consists of a regularly updated collection of evidence-based medicine databases including the Cochrane Database of Systematic Reviews (reviews of randomised controlled trials prepared by the Cochrane Collaboration).


Computed tomography – an X-ray technique used to examine the brain.

Cost-effectiveness analysis

An economic study design in which consequences of different interventions are measured using a single outcome, usually in natural units (for example, life-years gained, deaths avoided, heart attacks avoided, cases detected). Alternative interventions are then compared in terms of cost per unit of effectiveness.

Cost-utility analysis

A form of cost-effectiveness analysis in which the units of effectiveness are quality adjusted life years (QALYs).

Decompressive craniectomy

A surgical procedure for the treatment of raised intracranial pressure. A piece of the skull is removed to allow the swelling brain to expand.


Deep vein thrombosis.

Diagnostic accuracy

The degree to which a diagnostic (or screening) tool or procedure is able to distinguish between cases and non-cases. See also ‘sensitivity’, ‘specificity’, ‘negative predictive value’ and ‘positive predictive value’.


A difficulty in swallowing.


The surgical removal of plaque from a blocked artery to restore blood flow.


Face Arm Speech Test – used to screen for the diagnosis of stroke or TIA.


Fibreoptic Endoscopic Evaluation of Swallowing. A flexible nasendoscope is inserted through the nose to the throat to observe swallowing.


Fresh frozen plasma.


Guideline Development Group.


Gugging Swallowing Screen. A screen designed to identify patients with dysphagia and reduce the risk of aspiration.


Bleeding caused by blood escaping into the tissues.


Raised pressure within the skull.


Health Technology Assessment, funded by the NHS Research and Development Directorate.

Incremental cost

The cost of one alternative less the cost of another.

Incremental cost effectiveness ratio (ICER)

The ratio of the difference in costs between two alternatives to the difference in effectiveness between the same two alternatives.

Independent predictor

A variable whose value predicts the occurrence of an event independent of the values of other variables.


An area of cell death due to the result of a deprived blood supply.


International normalised ratio. A measure of the clotting ability of blood, usually following use of anticoagulant drugs. It is calculated as the ratio of the length of time it takes blood to clot over the time it would take the blood of a normal subject to clot.

Intracranial haemorrhage

A bleed in the brain as a result of a ruptured or bleeding blood vessel.


Middle cerebral artery.


A statistical technique for combining (pooling) the results of a number of studies that address the same question and report on the same outcomes to produce a summary result.

Methodological limitations

Features of the design or reporting of a clinical study which are known to be associated with risk of bias or lack of validity. Where a study is reported in this guideline as having significant methodological limitations, a recommendation has not been directly derived from it.

Modified Rankin Scale (mRS)

Six-point scale with 0 for no symptoms and 6 for death measuring the degree of disability or dependence in daily activities.


Magnetic resonance imaging – a non-invasive imaging technique allowing detailed examination of the brain.

MRI with DWI

Magnetic resonance imaging with diffusion-weighted imaging.


Malnutrition Universal Screening Tool. A screening tool comprising 5 steps which help identify which adults are malnourished or at risk of malnourishment.

Northern American Symptomatic Carotid Endarterectomy Trial (NASCET)

The NASCET and ECST (see below) methods both indicate the degree of stenosis as a percentage reduction in vessel diameter. The minimum diameter of the arteries caused by stenosis (which is the maximum point of blood constriction) is compared to another diameter that represents the normal diameter of the carotid arteries when the patient is healthy. NASCET includes a measurement taken along a point of the internal carotid artery in a healthy area well beyond an area of the bulb that was caused by stenosis.

European Carotid Surgery Trial (ECST)

The ECST formula includes the estimated normal lumen diameter at the site of the lesion, based on a visual impression of where the normal artery wall was before development of the stenosis.


The National Collaborating Centre for Chronic Conditions, set up in 2000 to undertake commissions from the NICE to develop clinical guidelines for the NHS.

Negative predictive value (NPV)

The proportion of individuals with a negative test result who do not have the disease.

NG feeding

Nasogastric intubation using a nasogastric tube which is inserted through the nose, past the throat and down into the stomach for the purposes of feeding.


National Health Service. This guideline is written for the NHS in England and Wales.


National Institute for Health and Clinical Excellence – a special health authority set up within the NHS to develop appropriate and consistent advice on healthcare technologies, and to commission evidence-based guidelines.

Non-significant (NS)

See ‘statistical significance’.


National Service Framework – a nationwide initiative designed to improve delivery of care for a related group of conditions.

Null hypothesis

The ‘no difference’ or ‘no association’ hypothesis that can be tested against an alternative hypothesis that postulates a difference or association that is non-zero.

Observational study

Retrospective or prospective study in which the investigator observes the natural course of events with or without control groups, for example cohort studies and case-control studies.

Odds ratio (OR)

A measure of treatment effectiveness. The odds of an event happening in the treatment group, expressed as a proportion of the odds of it happening in the control group. The ‘odds’ is the ratio of non-events to events.

Open-label study

In the context of study design, a study in which the physicians or investigators are not blinded to which patients are allocated to which treatment arm.


Pulmonary embolism – a blood clot in the lungs.


Percutaneous endoscopic gastrostomy/jejunostomy used for feeding. A gastroscope is used to insert a tube through the wall of the abdomen into the stomach.


Prothrombin complex concentrate.

Positive predictive value (PPV)

The proportion of individuals with a positive test result who actually have the disease.

p values

The probability that an observed difference could have occurred by chance. A p value of less than 0.05 is conventionally considered to be ‘statistically significant’.

Quality of life

Refers to the level of comfort, enjoyment and ability to pursue daily activities.

Quality of life-adjusted year (QALY)

A measure of health outcome which assigns to each period of time a weight, ranging from 0 to 1, corresponding to the health-related quality of life during that period, where a weight of 1 corresponds to optimal health, and a weight of 0 corresponds to a health state judged equivalent to death; these are then aggregated across time periods.


Randomised controlled trial. A trial in which people are randomly assigned to two (or more) groups: one (the experimental group) receiving the treatment that is being tested, and the other (the comparison or control group) receiving an alternative treatment, a placebo (dummy treatment) or no treatment. The two groups are followed up to compare differences in outcomes to see how effective the experimental treatment was. Such trial designs help minimise experimental bias.

Relative risk (RR)

The number of times more likely or less likely an event is to happen in one group compared with another (calculated as the risk of the event in group A, divided by the risk of the event in group B).


Recognition of Stroke in the Emergency Room – used to establish the diagnosis of stroke or TIA.


The proportion of individuals classified as positive by the gold or reference standard, who are correctly identified by the study test.

Sensitivity analysis

A measure of the extent to which small changes in parameters and variables affect a result calculated from them. In this guideline, sensitivity analysis is used in health economic modelling.

Side effect

An adverse event that occurs because of a therapeutic intervention.


A clinician whose practice is limited to a particular branch of medicine or surgery, especially one who is certified by a higher medical educational organisation.


The proportion of individuals classified as negative by the gold (or reference) standard, who are correctly identified by the study test.


Any national organisation, including patient and carers’ groups, healthcare professionals and commercial companies with an interest in the guideline under development.

Statistical significance

A result is deemed statistically significant if the probability of the result occurring by chance is less than 1 in 20 (p<0.05).


Abnormal narrowing of a blood vessel.


A metal mesh tube is placed in an artery or blood vessel to increase blood flow to an area blocked by stenosis.


The damaging or killing of brain cells starved of oxygen as a result of the blood supply to part of the brain being cut off. Types of stroke include Ischaemic stroke caused by blood clots to the brain or haemorrhagic stroke caused by bleeding into/of the brain.

Stroke mimics

A term used to describe other clinical conditions which can mimic a stroke and confound diagnosis. Examples of these include brain tumours, epilepsy or subdural haematosis. Neurologic abnormalities similar to a stroke can also be the result of imbalances of glucose, sodium and calcium.

Systematic review

Research that summarises the evidence on a clearly formulated question according to a pre-defined protocol using systematic and explicit methods to identify, select and appraise relevant studies, and to extract, collate and report their findings. It may or may not use statistical meta-analysis.

Technology appraisal

Formal ascertainment and review of the evidence surrounding a health technology, restricted in the current document to appraisals undertaken by NICE.


Transient ischaemic attack – a stroke which recovers within 24 hours of onset of symptoms.


A formation of a blood clot.


The use of drugs to break up a blood clot. Two examples of thrombolysis drugs are tPA and Alteplase.


Tissue plasminogen activator – a drug used for thrombolysis.

Venous stroke

The formation of a blood clot in the intracerebral veins and venous sinuses.


Videofluoroscopy is a test for assessing the integrity of the oral and pharyngeal stages of the swallowing process. It involves videotaping fluoroscopic images as the patient swallows a bolus of barium.


World Health Organization.

Copyright © 2008, Royal College of Physicians of London.

All rights reserved. No part of this publication may be reproduced in any form (including photocopying or storing it in any medium by electronic means and whether or not transiently or incidentally to some other use of this publication) without the written permission of the copyright owner. Applications for the copyright owner’s written permission to reproduce any part of this publication should be addressed to the publisher.

Bookshelf ID: NBK53297


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