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Scope and methodology

The need for a guideline

A number of recommendation and guidelines on the management of gastroenteritis in childhood
have been published. 16–22 However, this guideline is unique.
Some guidelines have focused on specific subgroups of children, such as those presenting to a
hospital setting. This guideline is intended to apply to children younger than 5 years in England
and Wales who present to a healthcare professional for advice in any setting. Importantly, it differs
from other guidelines in that it was developed using a set of important principles employed for all
NICE clinical guidelines. At the outset there was a process of national consultation to determine
the key areas of management that should be addressed and to define the exact ‘scope’ of the
guideline. Recommendations were based on the best available evidence whenever possible. A
systematic and thorough approach was employed to identify relevant research evidence and to
evaluate the available studies. For this guideline much of the best evidence is from developing
countries and must be interpreted in that light. As there are often important differences in the
baseline characteristics of the population, it cannot automatically be assumed that developing
country evidence is applicable to a UK setting. For example, malnutrition may often be an
important clinical feature of gastroenteritis in developing countries, leading to markedly different
outcomes than would be observed in a developed country setting. In interpreting developing
country evidence, relative effect measures, especially from large meta-analyses, are generally
more stable than absolute measures of effect. Variation in baseline characteristics means that
evidence based on absolute measures cannot reliably be applied to a developed country setting.
However, even relative measures of effect need to be interpreted with a view as to whether
the context is sufficiently similar: ‘Is my patient so different from those in the trial that its
results cannot help me make my treatment decision?’ This very much reflected the Guideline
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Development Group (GDG) approach in discussing evidence for this guideline from developing
country settings.
The GDG responsible for the guideline recommendations was constituted so as to include
individuals with a wide range of relevant personal and clinical expertise. Various authors have
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commented on the difficulty of implementing guideline recommendations. In part this may
reflect the practical difficulties of following recommendations in a real setting – taking account
of practical impediments and professional or parental perceptions or views. The GDG included
parents with personal experience of caring for ill children. It included doctors and nurses
working in the community, and in primary, secondary and tertiary healthcare settings. It was
supported by a professional ‘technical team’ including information scientists, expert research
staff and health economists. External expert advisers were appointed to assist the GDG in its
consideration of various complex technical matters. External peer reviewers commented on the
guideline during its development. Inevitably, evidence was sometimes limited or non-existent
and, in such situations, recommendations were based on GDG consensus opinion. The GDG
was able to make recommendations on priority areas for future research. Lastly, there was a
process for consultation with ‘stakeholder’ organisations on a draft version of the guideline prior
to publication in its final form.

1.2 Aim of the guideline

Clinical guidelines have been defined as ‘systematically developed statements which assist
clinicians and patients in making decisions about appropriate treatment for specific conditions’.
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The guideline has been developed with the aim of providing guidance on the diagnosis, assessment
and management of children younger than 5 years with acute diarrhoea and vomiting caused by
gastroenteritis in England and Wales.

1.3 Areas within the scope of the guideline

Population

• Infants and young children from birth up to their fifth birthday presenting to healthcare
professionals with acute diarrhoea (lasting 14 days or fewer) due to gastroenteritis, on its
own or with vomiting.

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