The gold standard for blood pressure accuracy—which is necessary for the proper diagnosis and management of hypertension—had long been the mercury sphygmomanometer. But as it was phased out and new automated devices came to market, there was no easy way to know which of the hundreds of BP devices available have been tested for accuracy compared to the gold standard. In turn, it is difficult to trust readings if the device’s accuracy is unknown. That uncertainty may lead to hesitation in diagnosing and treating hypertension.
To address this gap, hypertension experts began to meet in 2015 to create a framework for demonstrating that a BP measurement device could produce clinically accurate results. Working closely with these experts, the AMA formalized a set of criteria to aid in determining which BP devices available in the U.S. have been validated for clinical accuracy and tested against the gold standard.
At the launch of the US Blood Pressure Validated Device Listing (VDL™) in 2020, 16 BP measurement devices met the requirements to be listed as clinically accurate after the testing data was submitted by their manufacturers for review. Now that number has grown to 57, and includes home and in-office upper arm devices, wrist cuff devices, community kiosks and 24-hour ambulatory monitors. Yet the criteria still need more widespread industry adoption.
Out of 100 best-selling blood pressure devices sold by Amazon, 81% had not undergone adequate clinical validation testing, according to a study published last month in the Journal of Hypertension.
“The bottom line is most devices for sale in the U.S. have not been validated for clinical accuracy,” said Michael Rakotz, MD, vice president of health outcomes at the AMA. “There is a need for the VDL to make it easier for anyone looking for an accurate device be able to find one.”
Here is why having a validated device listing matters when it comes to BP control.
A way to accurately assess BP status
Making the VDL publicly available is one key part of the AMA’s larger effort to improve blood pressure control rates nationwide.
“We strongly believe—that measuring blood pressure accurately is essential for diagnosing and treating hypertension,” Dr. Rakotz said, emphasizing “that is why accurate blood pressure measurement is the foundation of the AMA MAP BP™ quality improvement program.”
“Without it you won’t be able to accurately assess a person’s blood pressure,” he said. “By using devices that are shown to be accurate, you’re more likely to correctly classify BP status to know who has hypertension and to help guide treatment.”
AMA MAP BP is a leading evidence-based quality improvement program that helps provide a clear path to significant, sustained improvements in BP control. With AMA MAP BP, health care organizations can increase BP-control rates quickly. The program has demonstrated a 10% increase in BP control in six months with sustained results at one year.
It's an easy-to-access resource
“Whoever is looking for a BP measurement device should be able to know whether or not it provides clinically accurate readings. That's important,” Dr. Rakotz said. “The goal is to make it easily accessible for clinicians to select devices for use in the office or to recommend to patients for use at home.”
While there were similar lists available in other countries, they have been difficult to navigate for the U.S. audience.
“What we learned from our experience working with health systems is that neither physicians nor patients have an easy way to see a list of validated devices,” he said. “And because the device names and model numbers vary from country to country, we thought that it was important to have a list for devices being sold in the United States.”
There are no conflicts of interest
Devices are considered for listing through an independent review process, where an expert panel of 13 physicians reviews submitted device testing data against the criteria for validation of clinical accuracy.
Additionally, the AMA does not receive funding or application fees from external entities or device manufacturers and does not play a role in the review or approval of devices for listing. These are important principles to maintain objectivity and integrity of the VDL.
"It’s also important that the VDL is a trustworthy resource curated and managed by clinical and measurement experts with no conflicts of interest,” said Dr. Rakotz.
“Again, we wanted there to be an easy to access list of devices that have been tested for accuracy so that users of the device, or purchasers of the device will know that the device has been tested,” he explained.
“If a device is on the list, it means that it has met strict testing criteria for measurement accuracy.”
Dr. Rakotz also noted that “If a device is not on the list, that doesn’t necessarily mean it’s not accurate. It may mean that the manufacturer has not yet submitted data to be reviewed to determine if it meets the criteria for validation for clinical accuracy.”
