Comparison of a new portable electronic sphygmomanometer (Copal UA251) with the Hawksley random zero machine

The performance of the Copal Digital Sphygmomanometer UA251, a new semi-automatic blood pressure recorder, was evaluated by comparing the results obtained simultaneously and on the same arm using the standard zero-muddler sphygmomanometer. The study was performed on 67 hypertensive patients displaying a wide range of blood pressure and arm circumference. The agreement was acceptable with a mean difference, using the first set of readings of -0.45 (S.D. 2.9, range 8 to -5) and -0.95 (S.D. 2.6, range 6 to -4) mmHg for the systolic and diastolic pressures respectively. The repeatability of the Copal machine was also good; the mean difference between first and second measurements was -0.21 (S.D. 3.4, range 11 to -11) and -0.69 (S.D. 1.9, range 5 to -8) mmHg for systolic and diastolic readings respectively. Since this electronic machine has an acceptable accuracy, is readily portable, simple to use and relatively inexpensive, it seems suitable for use both in clinics and for more frequent monitoring of blood pressure throughout the day.