Page 18 - 15Diarrhoeaandvomiting

Glossary of terms

Hyponatraemia An electrolyte disturbance in which the plasma sodium concentration is less
than 135 mmol/l.
Hypovolaemic shock A state of decreased blood volume or more specifically of blood plasma volume
that results in inadequate circulation of blood to the body tissues.
I² A quantitative measure of statistical heterogeneity which describes the
percentage of variability in the study results or effects of estimates that is
beyond the amount expected by chance. Generally, a value greater than 50% is
considered to represent substantial heterogeneity.
Immunocompromised A congenital or acquired condition in which the immune system is functionally
impaired, resulting in an increased risk of infection.
Incidence Incidence and prevalence are tools to describe how common a disease or an
event/outcome is with reference to the size of population. Incidence measures
the frequency of disease or an event/outcome in new cases only. The two
commonly used measures of incidence are the risk or absolute risk and the rate.
Inclusion criteria See selection criteria.
In-depth interview A qualitative research technique. It is a face-to-face conversation between a
researcher and a respondent with the purpose of exploring issues or topics in detail.
It does not use pre-set questions, but is shaped by a defined set of topics or issues.
Infant A child younger than 1 year.
Inflammatory bowel disease A group of chronic intestinal diseases characterised by inflammation of the
gastrointestinal tract. The two most common types of inflammatory bowel
disease are Crohn’s disease and ulcerative colitis.
Intention-to-treat analysis A strategy used in randomised controlled trials whereby data from study
participants are analysed according to the group to which they were initially
randomly allocated, regardless of whether or not they had dropped out, fully
complied with the treatment, or crossed over and received the alternative
treatment. Intention-to-treat analyses are favoured in assessments of clinical
effectiveness as they mirror the non-compliance and treatment changes that are
likely to occur when the treatment is used in practice.
Internal validity Refers to the integrity of the study design or the extent to which the study design
was successful in preventing bias. See also methodological quality.
Intervention Healthcare action intended to benefit the patient, for example drug treatment,
surgical procedure, psychological therapy, etc.
Intervention or A group of participants in a study who receive a specific healthcare intervention.
experimental group See also control group.
Intestinal obstruction A blockage of the intestine typically resulting in symptoms such as abdominal
pain and vomiting.
Intravenous fluid therapy The administration of fluids directly into the venous circulation.
(IVT)
Intussusception A condition in which a part of the intestine prolapses (telescopes) into another
immediately adjacent section of the intestine, typically resulting in symptoms of
intestinal obstruction. It can lead to gangrene of the affected gut segment.
Kwashiorkor A state of severe protein malnutrition marked by lethargy, growth restriction,
anaemia, oedema, potbelly, skin depigmentation, and hair loss or change in hair
colour.
Level of evidence See evidence level.
Leucocytosis An abnormally high level of white cells (leucocytes) in the blood.
Likert scale A survey method of measuring attitudes that asks respondents to specify their
level of agreement with a statement.
Literature review A process of collecting, reading and assessing the quality of published (and
unpublished) articles on a given topic.
Longitudinal study A type of observational study that follows a group of people at more than one
point in time or where repeated observations are made. (This type of study
contrasts with a cross-sectional study, which observes a defined set of people at
a single point in time.)

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