Some problems of therapeutic trials in hypertension.

It is strongly recommended that a scientific protocol for controlled therapeutic trials in hypertension should include, inter alia, the following: 1. A definition of the level(s) of blood pressure which indicate hypertension (systolic and/or diastolic), preferably related to age and sex. 2. The criteria for defining the type of hypertension (e.g., essential, renovascular, etc.). 3. A statement relative to which diastolic level is to be recorded: phase IV ("muffling") and/or phase V ("disappearance"). 4. Information on the sizes of sphygmomanometer cuffs to be used. 5. A statement of which arm is to be used (throughout the study). 6. A statement of postures in which blood pressure is to be measured (supine, sitting, standing). 7. Information on the conditions under which pressures are to be recorded (e.g., "casual," "near-basal," etc.) and the duration of rest before recording. 8. Details of the times of day at which measurements are to be taken.9. A statement on the method of establishing baseline readings (e.g., mean of three successive readings) and the acceptable degree of variability (e.g., +/- 10 mm Hg). 10. A definition of "endpoints" (e.g., diastolic pressure less than upper limit of normal; reduction in diastolic pressure greater than 10 mm Hg).