Figure 1.

Serum potassium measurements among patients who are code positive and code negative for hyperkalaemia (when the code was considered in the format ‘all diagnoses’). For both presentation to an emergency department and at hospital admission, patients who for positive for the hyperkalaemia code had a significantly higher serum potassium measurement than patients who were code negative. The boxes represent the IQR (50% of the values). The line across the box indicates the median. The star indicates the mean. The whiskers extend to the 95th and 5th percentile.