Figure 1.

Percentage of false positive test results (and 95% confidence interval) at 100% sensitivity in using a traditional interpretation of fractionated plasma metanephrine measurements or an age-adjusted metanephrine score. Legend – Pmet(s), fractionated plasma metanephrine measurements; traditional fractionated plasma metanephrine measurements are considered positive if the metanephrine fraction is greater than or equal to 0.5 nmol/L or the normetanephrine fraction is greater than or equal to 0.9 nmol/L; an age-adjusted metanephrine score is positive if it is greater than -1.4752. The difference between false positive rates is statistically significant with p < 0.001 using McNemar's test.