Short report: Accuracy of the Profilomat ambulatory blood pressure measuring system determined by the British Hypertension Society Protocol

Abstract

Objective: To evaluate the Profilomat monitor for ambulatory blood pressure measurement according to the British Hypertension Society (BHS) protocol. Design: The BHS protocol consists of six phases: I, observer training and assessment; II, before-use interdevice variability assesment; Ill, in-use assessment; IV, after-use interdevice variability assessment; V, device validation; and VI, preparation of report. Method: Three Profilomat recorders passed the before-use interdevice variability test, after which they entered the in-use phase during which the three recorders are worn by subjects over 24 h. In 12 recording days the Profilomat failed to achieve the required 70% valid recordings. This was identified as being due to the inability of the Profilomat to take a second measurement when the first one failed, and when this facility was provided the Profilomat fulfilled the in-use requirement and the three devices subsequently passed the after-use interdevice variability test. The main validation test was carried out in 86 subjects with a wide range of pressures, the results being analysed according to the BHS grading system from A to D. Results: The Profilomat acheived grade B rating for systolic blood pressure and grade A for diastolic blood pressure, and satisfied the criteria for acccuracy of the Association for the Advancement ~f Medical lnstrumentation (AAMI) with a mean difference (+ SD) for systolic pressure of 3+ 5 mmHg and If 5 mmHg for diastolic pressure. Subject acceptability was good and the manufacturer's manual was satisfactory. Conclusion: On the basis of these results, the Profilomat can be recommended for ambulatory blood pressure measurement in clinical practice.