VA COOP 1982.

Methods	Multicentre study Randomisation: described as randomised controlled trial, but method of allocating participants to treatment not described Blinding: participants, providers, and assessors blinded Loss to follow‐up: 8% Mean duration of follow‐up: 12 months Participants withdrawn from the study for uncontrolled BP not included in the analysis
Participants	Geographic region: USA Study setting: hospital Number of participants: 683 (all men) Age range: 21 to 65 years (mean: 49.6 years) Race: 43% white and 57% black BP at entry: DBP 95 to 104 mmHg Comorbid conditions: not described
Interventions	Beta‐blocker group: Propranolol 40 mg twice daily, increasing to 640 mg/day Diuretic group: Hydrochlorothiazide 25 mg twice daily, increasing to 200 mg/day Participants still on assigned baseline therapy at study end: beta‐blocker group, 39%, diuretic group: 52%
Outcomes	Total mortality Cerebrovascular disease CHD
Notes	Participants were withdrawn from the study if, on any follow‐up visit, DBP ≥ 120 mmHg
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Not described
Allocation concealment (selection bias)	Unclear risk	Not described
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Participants and providers blinded
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Outcome assessors blinded
Incomplete outcome data (attrition bias) All outcomes	Low risk	"A total of 73 (10.7%) of the patients were dropped from the study after randomization. Of these, 42 (57.5%) were in the propranolol group and 31 were taking hydrochlorothiazide. The difference was not significant" Analyses by intention‐to‐treat
Selective reporting (reporting bias)	Unclear risk	No access to study protocol.
Other bias	Unclear risk	Other antihypertensive drugs added to randomly allocated treatment to control BP. The observed effects may equally have resulted from the different additional drugs.

ACE: angiotensin‐converting enzyme; BP: blood pressure; CHD: coronary heart disease; CHF: congestive heart failure; CVD: cardiovascular disease; DBP: diastolic blood pressure; LVH: left ventricular hypertrophy; MI: myocardial infarction; SBP: systolic blood pressure; SD: standard deviation; SR: sustained release; TIA: transient ischaemic attack.