Accuracy of blood pressure monitors available in high street pharmacies

The aim of this study was to assess the accuracy of automated blood pressure monitors on sale to the UK general public. We conducted static pressure accuracy testing on all compatible (19 out of 22 available) blood pressure monitors available for sale in pharmacies within the city of Oxford, UK, and tested two devices for accuracy in measurement of systolic and diastolic blood pressures in 21 adults. The devices showed good accuracy when measuring static pressure in laboratory bench testing, with the median error per device ranging from -2.2 to +1.2 mmHg; however, the two devices tested performed worse in vivo than in laboratory tests, with median errors as high as 6 mmHg. The monitors showed good accuracy in static pressure testing, with a lack of correlation between monitor price and accuracy. However, higher error rates seen during in-vivo testing of a subset of monitors may indicate that static testing may not be appropriate for routine accuracy assessment of these monitors.