Specificity and sensitivity of blood pressure measurements.

Specificity and sensitivity of a biological test describe the ability of the test to exclude false and to include true positives. A method is described for estimating such values for blood pressure measurement. Estimated values are given for various cut-off levels of the diastolic blood pressure. The method indicates that the optimal cut-off for defining hypertension is found to be at the blood pressure level where the specificity is appraoching 100% and where the sensitivity is about 20%. For example, for males aged 50--59, this is obtained at the diastolic blood pressure level of 105--110 mg Hg.