2. Baseline characteristics (I).

Trial	Intervention(s) and comparator(s)	Description of participants	Nationality	Setting	Ethnic groups (%)	Duration of disease (mean years (SD))	Antihypertensive treatment (%)
Cohen 1991	diet	hypertensive and obese patients stratified by residents (residents not patients were randomised to intervention or control group)	USA	model family practice unit (Pittsburgh)	‐	‐	(number of medications: 1.6)
	no diet				‐	‐	(number of medications: 1.2)
Croft 1986	diet	newly diagnosed hypertensive and obese patients	Great Britain	outpatient clinic (1 urban group practice)	‐	newly‐diagnosed patients	0
	no diet				‐		0
DISH 1985	diet	people who were previously enrolled in the HDFP treated with antihypertensive drugs and who had sufficiently controlled hypertension. The dietary change on the return of hypertension after withdrawal of prolonged antihypertensive therapy (DISH) included 7 treatment arms; the results of 2 of those arms met the inclusion criteria for this review (hypertensive and obese patients with either dietary intervention or not)	USA	outpatient clinic	Black (62)	at least 5 years	100
	no diet				Black (70)		100
Jalkanen 1991	diet	overweight hypertensive patients (selected from files)	Finland	outpatient clinic (2 hypertension clinics in Finland)	‐	‐	50
	no diet				‐	‐	50
ODES 1995	diet	men and women ≥ 40 years old from screening programme for cardiovascular risk factors in Oslo (Norway) since 1981; participants were post‐hoc divided in tertiles according to DBP (tertile 1 DBP > 91 mm Hg, tertile 2 DBP 84 to 91 mm Hg, tertile 3 DBP < 84 mm Hg); only subgroups of tertile 1 (DBP > 91 mm Hg) will be reported here	Norwegian	outpatient clinic	‐	‐	0
	no diet				‐	‐	0
	diet + physical activity				‐	‐	0
	no diet + physical activity				‐	‐	0
Ruvolo 1994	diet	overweight hypertensive patients on 10 mg amlodipine daily	Italian	outpatient clinic	‐	‐	100 with amlodipine 10 mg
	no diet				‐	‐	100 with amlodipine 10 mg
TAIM 1992	diet + placebo	obese hypertensive patients	USA	outpatient clinic at 3 university hospitals (Bronx (New York), Birmingham (Alabama), Jackson (Mississippi))	White (67) Black (33)	‐	0
	no diet + placebo				White (65) Black (35)	‐	0
	diet + atenolol				White (67) Black (33)	‐	100
	no diet + atenolol				White (67) Black (33)	‐	100
	diet + chlorthalidone				White (67) Black (33)	‐	100
	no diet + chlorthalidone				White (67) Black (33)	‐	100
TONE 1998	diet without salt restriction	elderly, obese, and hypertensive patients; participants were assigned to active intervention: sodium reduction (S+), or weight loss, or sodium reduction (S+) and weight loss vs usual care	USA	outpatient clinic	White (73) African American (26)	11.3 (9.2)	100
	no diet without salt restriction				White (68) African American (32)	11.6 (8.0)	100
	diet + salt restriction				White (76) African American (24)	11.9 (9.5)	100
	no diet + salt restriction				White (70) African American (30)	11.9 (9.3)	100