References (country)	Design	Subject characteristics at baseline	UNa (mmol/24 h)	BP measurement SBP/DBP (mm Hg)
He et al. (2015) (China) School‐EduSalt	Study design: cluster‐randomised Run‐in type: none Intervention type: counselling N participants randomised/completed: 279/274 Duration: 14 weeks	% boys G1: 47.5 G2: 48.6 Age (mean ± SD, years) G1: 10.0 ± 0.5 G2: 10.2 ± 0.5 BMI (mean ± SD, kg/m 2 ) G1: 17.1 ± 3.2 G2: 16.7 ± 2.7 Ethnicity: NR BP status: NR 24‐h UK (mean ± SE, mmol) G1: 23.5 ± 0.9 G2: 25.4 ± 0.9 Energy intake: NR	Type: multiple 24 h Mean ± SE Beginning of intervention G1: 124.2 ± 5.1 G2: 116.7 ± 5.2 End of intervention G1: 112.2 ± 5.1 G2: 137.2 ± 5.2	Type: point office, sitting Mean ± SE Beginning of intervention G1: 106.2 ± 1/67.0 ± 1.1 G2: 106.2 ± 1/66.8 ± 1.1 End of intervention G1: 110 ± 1/69.4 ± 1.1 G2: 110.6 ± 1/70.2 ± 1.1
Miller et al. (1988) (USA)	Study design: parallel Run‐in type: low sodium diet Intervention type: feeding N participants randomised/ completed: 88/NR Duration: 4 weeks	% boys: NR Age (years): NR BP status: NT Ethnicity: NR 24‐h UK (mean, mmol) G1: 35.3 G2: 36.7 Energy intake: NR	Type: multiple 24 h Mean Beginning of intervention NR End of intervention G1: 44.4 G2: 72.1	Type: point office, sitting Mean Beginning of intervention NR End of intervention G1: 91.7/53.0 G2: 92/52.9

BMI: body mass index; BP: blood pressure; DBP; diastolic blood pressure; G1: group 1 (‘low’ sodium); G2: group 2 (‘high’ sodium); mm Hg: millimetre of mercury; N: number; UNa: sodium urinary excretion; NR: not reported; NT: normotensive; SBP: systolic blood pressure; SD: standard deviation; SE: standard error; UK: potassium urinary excretion.