The differential diagnosis of hypernatraemia in children, with ...

The Diagnosis of Salt Poisoning Leading to Hypematraemia in Children – September 2009
Eligible papers with a study design other than a case report were critically appraised
for methodological quality using the standard SIGN checklists 10 where appropriate. The
guideline lead agreed whether each paper was of a sufficient methodological quality to
inform the evidence review for the section to which it had been allocated.
Publications other than case reports were critically appraised. Case reports of accidental
and non-accidental poisoning of children were reviewed using the procedure described
below.
Synthesising the evidence
The findings were summarised by the guideline lead into an evidence summary as a series
of statements. The draft and final versions of the guideline were presented to GDG for
comment.
Formulation and grading of recommendations
A spreadsheet containing extracted data for included studies was used to develop evidence
statements and recommendations.
The researcher graded each evidence statement according to the level of evidence upon
which it was based using an adaptation 3 of the Oxford Centre for Evidence-based Medicine
hierarchy of evidence table 11 presented in the table that follows. The purpose of a hierarchy
is to reflect the effectiveness of the study design to answer a particular research question.
For example, questions relating to prognosis, the highest possible level of evidence is
a cohort study (evidence level 1), which would equate to a grade A recommendation if
relevant to the clinical question. The guideline lead independently assessed the accuracy
of the grading. Disagreements were resolved through discussion.
3
For the purposes of this guideline, case reports and case series that had been subjected to peer
review were considered to be level 4 evidence
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