Table 1.

Baseline characteristics for participants in the IG and CG

Characteristic*	IG			CG			P-value†
	n	Mean	se	n	Mean	se
Participants	573			614			–
Schools	21			32			–
Classes	31			46			–
Participant per school
n		27·3	18·2‡		19·2	15·0‡	–
Range		7–80			5–75
Age in years	565	8·707	0·02	608	8·637	0·02	0·033
Male
n	572	308		613	311		0·158
%	572	53·8		613	50·7
Beverage consumption; glasses/d
Water (tap)	540	3·94	0·13	591	3·14	0·11	0·003
Total water (tap and mineral)	540	4·91	0·13	591	4·31	0·12	0·286
Juice	540	1·75	0·09	591	1·67	0·08	0·642
Soft drinks	540	0·60	0·09	591	0·52	0·05	0·339
Tap water relative to total drinking volume (%)	540	48·05	1·35	591	40·89	1·28	0·777
Total water relative to total drinking volume (%)	540	58·89	1·26	591	55·55	1·23	0·725

IG, intervention group; CG, control group; sd, standard deviation; se, standard error of the mean.

^*Unadjusted values on an individual level.

^† P-values for differences between the IG and CG, with adjustment for clustering according to school and classroom.

^‡ sd.