Table 2.

Medians and reference intervals (2.5 and 97.5 percentiles) for plasma normetanephrine and metanephrine according to gender and six age groups

	N	Age (years) Median	Normetanephrine (nmol/L)			Metanephrine (nmol/L)
			Median	97.5 percentile	2.5 percentile	Median	97.5 percentile	2.5 percentile
All subjects	1226	41.0	0.298	0.706	0.120	0.147	0.325	0.031
Women	679	40.2	0.293	0.710	0.125	0.132*	0.315	0.035
Men	547	41.0	0.302	0.704	0.120	0.170†	0.329	0.030
5–17 y	116	13.2	0.248*	0.470	0.048	0.172†	0.333	0.045
18–29 y	229	24.7	0.251*	0.588	0.118	0.137*	0.264	0.034
30–39 y	232	34.5	0.273*†	0.618	0.126	0.138*	0.304	0.014
40–49 y	283	45.0	0.300†	0.687	0.115	0.147*†	0.324	0.031
50–59 y	241	53.0	0.362§	0.747	0.136	0.157†	0.375	0.046
>60 y	125	65.4	0.355§	1.047	0.137	0.163†	0.358	0.051

Presence of different symbols (*^†§) indicates differences (P < 0.005) in normetanephrine or metanephrine between men and women or among different age groups