Study designs of evaluations included in the review
Controlled trials. Except for non comparative trials, the design of studies included in the review was randomised, double-blind and, where necessary, double-dummy. The length of follow up of included studies ranged from 4 to 52 weeks.
Specific interventions included in the review
Nebivolol (0.5, 1.0, 2.5, 5.0 and 10mg) was compared with placebo, the beta-blockers atenolol (50 or 100mg) and metoprolol (100mg) and other classes of antihypertensive agents including calcium antagonists (nifedipine 20mg) and angiotensin converting enzyme (ACE) inhibitors (lisinopril 2.5-10mg, enalapril 10mg). The drug was also investigated in combination with hydrochlorothiazide (12.5 or 25mg) or enalapril (10mg)
Participants included in the review
Patients aged 18 to 78 years with essential hypertension with or without comorbid conditions. The mean age range was about 52 to 59 years. Where stated, patients had mild to moderate hypertension (defined as supine/siting diastolic blood pressure (DBP)>/=95 and </=120mm Hg after washout/placebo run-in period.
Outcomes assessed in the review
Outcomes were not defined a-priori. The primary efficacy end-point for included studies was the change from baseline in supine or sitting DBP. Other end-points included change from baseline in supine or sitting systolic blood pressure (SBP) and changes in standing DBP and SBP, which were generally assessed after 2 minutes in the upright position and after the siting/supine measurement had been taken. Where stated, response to therapy was defined as a reduction in sitting/supine DBP to </= 90mmHg or a fall from baseline values of 10% or of >/= 10mmHg.
How were decisions on the relevance of primary studies made?
Inclusion of studies was based mainly on the methods section of the trials. When available, large, well controlled trials with appropriate statistical methodology were included. No further information was presented on how decisions on the relevance of primary studies were conducted.