A novel and simple protocol for the validation of home blood pressure monitors in clinical practice

BACKGROUNDS: Although the European Society of Hypertension International Protocol for the validation of blood pressure (BP) measuring devices has simplified the validation protocol, it is still not feasible for use in routine clinical practice. OBJECTIVES: We sought to devise a method for validating individual home blood pressure (HBP) monitors that is simple enough for use in routine clinical practice. METHODS: We consecutively enrolled 92 hypertensive patients (mean age: 63.2±14.6 years) from the hypertension clinic at the Columbia University Medical Center. Five sequential same-arm BP readings were recorded by a physician: first (D1), second (D2), and fourth (D3) using an HBP device; the third (M1) and fifth (M2) readings were taken manually using a mercury sphygmomanometer. Analyses focused on the absolute values of the differences in the BP values. In step 1, differences D2-M1, M1-D3, and D3-M2 were calculated and if two of three BP differences were within 5 mmHg (or 10 mmHg), the monitor 'passed'. When a monitor failed step 1, if either the difference between M1 and the average of D2 and D3, or the difference between D3 and the average of M1 and M2 was within 5 mmHg (or 10 mmHg), it was judged to have 'passed'. RESULTS: We used only systolic blood pressure to simplify the protocol. In step 1, the number of monitors in which two of three BP differences were within 5 mmHg was 43 (46.7%) and those within 10 mmHg was 73 (79.4%) of 92 total monitors. Of those that failed the 5 mmHg criterion of step 1 (N=49), 20 passed step 2. Therefore, a total of 63 monitors (68.5%) fulfilled the 5 mmHg criteria. Of 19 monitors that failed step 1 using the 10 mmHg criterion, 12 fulfilled the 10 mmHg criterion for step 2, resulting in 85 of the 92 (92.4%) monitors passing the test. CONCLUSION: This simplified validation protocol may be of value for the routine evaluation of HBP monitors in clinical practice.