Preliminary evidence was identified using literature considered relevant by the National High Blood Pressure Education Program. A search of more recent literature was conducted on Medline prospectively using the major keywords of: hypertension, human adults, English language, clinical trials, guidelines, and published since 1/1/99. Terms used for specific topic searches within the major key words included: alpha 1 blocker, angiotensin converting enzyme inhibitors, angiotensin II receptor antagonist, beta blockers (selective and non-selective), calcium channel blockers (dihydropyridine and non-dihydropyridine forms), centrally acting alpha-2 agonist, diuretics (thiazide and non-thiazide, loop, potassium-sparing), vasodilator, avoidance (alcohol, stress, tobacco), blood pressure monitoring (ambulatory, home), dietary (caffeine, calcium, garlic, magnesium, onion, potassium, sodium), disease-based management (brain, cardiac, eye, kidney, peripheral vascular), and exercise. Detailed search terms and strategy available from the guideline developer upon request.
The search was conducted in components each keyed to a specific causal link in a formal problem structure (available from the guideline developer upon request). The search was supplemented with very recent information available to expert members of the panel, including abstracts from recent meetings and results of clinical trials. Negative trials were specifically sought. The search was a single cycle.