Figure 2.

Funnel plot showing consistency between OPCS mode of delivery code and delmeth code for English NHS trusts (2009/10). The English average was calculated by dividing the number of records with consistent mode of delivery recorded in both fields by the total number of records containing information about mode of delivery in both fields.

Knight et al. BMC Health Services Research 2013 13:200   doi:10.1186/1472-6963-13-200
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