Table 2.

Sodium, potassium and iodine excretions based on 24 h urine collections in Doetinchem, the Netherlands, in 2006 and 2010

	Overall						Men						Women
	n	Mean	sd	P50	P25–P75	P value*	n	Mean	sd	P50	P25–P75	P value*	n	Mean	sd	P50	P25–P75	P value*
Na excretion (mmol/d)
2006	317	148	55	141	109–179		137	164	55	160	117–206		180	136	51	128	101–159
2010	342	148	58	139	107–178	0·75	154	174	63	163	126–212	0·24	188	128	43	122	96–154	0·11
K excretion (mmol/d)
2006	317	62	23	59	47–74		137	70	26	69	54–82		180	57	18	55	43–66
2010	342	68	23	64	53–79	0·0005	154	76	26	72	58–89	0·008	188	61	18	60	50–71	0·03
Na:K
2006	317	2·5	0·9	2·4	1·9–3·1		137	2·5	0·9	2·3	1·9–3·0		180	2·5	0·9	2·5	1·9–3·1
2010	342	2·3	0·9	2·2	1·7–2·7	<0·0001	154	2·4	0·9	2·3	1·9–2·8	0·14	188	2·2	0·9	2·1	1·6–2·5	<0·0001
Iodine excretion (μg/d)
2006	317	265	150	236	165–313		137	295	163	265	203–332		180	245	137	210	148–300
2010	342	183	91	165	119–227	<0·0001	154	216	106	202	136–270	<0·0001	188	157	65	147	108–193	<0·0001

P50, 50th percentile (median); P25–P75, 25th–75th percentile (interquartile range, IQR).

*P value for the comparison with the corresponding group in 2006.