A5V4d

Health economics
Figure 11.1 Decision tree for analysing the impact of changing referral patterns for a child with fever without
source
Data required for the model
In order to make this analysis viable, the decision tree required specific data which the GDG thought
might be available in some form, through either the published literature or in unpublished data such as
national (or even local) audit data. A table with all the key model parameters was circulated among
the GDG members to try to locate this data. At the same time, the GDG members were asked
whether they could arrive at some consensus about the values required for the model from their
collective expert opinion.
As the discussion progressed, it was agreed that the meaningful comparison of referral patterns
required other data that would be very hard to obtain either from published sources or from GDG
consensus.
A number of key assumptions in the model could not be agreed upon. The first was that the outcomes
of care would be worse if treatment was delayed by sending a child home, either from primary care or
from secondary care with undiagnosed SBI. Nor was it clear that the costs of care would be
substantially different if there were a delay in treatment. It was not possible to estimate the impact that
such a delay would have on final outcomes (the death rate) or costs because of the uncertainty
around the natural history of specific serious bacterial diseases such as meningitis. Also, it was not
possible to agree upon the proportion of children with fever that are currently referred for primary
care.
It became apparent after two GDG meetings that it was not possible to reach a consensus on the data
required to populate the model, especially because the model considers all forms of SBI and no one
specific diagnosis, such as meningitis or pneumonia. Also, since the guideline focused on diagnosis
and initial management of SBI only, it would be difficult to obtain reliable data on the number of
children alive and well or not alive following detection and initial management of SBI, without looking
at treatment and longer term outcomes.
A further problem was the lack of baseline data on the underlying prevalence of SBI in the population.
The most uncertain data of all was the estimate of the proportion of cases of SBI that might be missed
by sending children home without further tests, in both primary or specialist care settings.
Some data were available from two published studies, one American 243 and one from the UK.121
Table 11.6 below indicates the data that could be used in the model (part I) and the gaps where no
data could be found (part II).
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