Why accuracy in BP measurements has never mattered more.
When Dr. Thomas Schwieterman talks about blood pressure, he’s really talking about the future of healthcare. As Vice President of Clinical Affairs and Chief Medical Officer at Midmark Corporation, he has seen the impact that a single, seemingly simple measurement can have on the trajectory of chronic disease, provider performance, and even national health economics.
And yet, blood pressure (BP) – the vital sign that influences more diagnoses and treatment decisions than almost any other – is among the most commonly mismeasured.
“Errors in BP measurement, unfortunately, are too common,” Dr. Schwieterman said. In clinics across the country, clinicians rush through the reading with patients “with feet dangling from a tall table, over a shirt sleeve and immediately upon entry into the room.” These shortcuts, long regarded as harmless, have turned out to be anything but.
What’s at stake is not just accuracy. It’s whether tens of millions of patients are treated appropriately – or treated unnecessarily.
The ripple effect of the SPRINT study
The turning point, Dr. Schwieterman explains, came nearly a decade ago with the landmark SPRINT study. “Since the SPRINT study was published, there has been a consistent flow of clinical science that affirms the importance of both accurate BP acquisition and proper hypertension management,” he said.
SPRINT revealed that lowering systolic blood pressure by just 10 mmHg dramatically reduced the risk of heart disease, heart attacks, and strokes. “If a patient’s BP is maintained below 130/80, about 25% of adverse cardiovascular events could be avoided,” he noted.
But this discovery came with a paradox. By lowering the threshold for what qualifies as hypertension, “nearly 40 million more Americans would be classified as having high BP.” Overnight, more than half the U.S. population could be considered hypertensive.
With so many more patients now flagged as potentially at risk, the margin for error shrank. False high readings suddenly meant tens of millions of people might be put on costly, unnecessary medication – all because of improper chair height, unsupported limbs, crossed legs, a full bladder, or conversation during the test.
“To avoid patients getting unnecessary medication with false positive high numbers, it became even more important for providers to capture this routine measurement exactly to protocol,” he said.
Old habits, new science
Blood pressure has long been viewed as a quick, routine task – one of the first skills healthcare workers learn. But that familiarity is part of the problem.
“Taking a BP is often one of the first things clinicians of all levels learn in their training, and it has the reputation of being trivial in nature,” he explained. Asking seasoned professionals to change their technique is “similar to asking a professional golfer to relearn how to complete a 2-foot putt or an NBA star how to shoot a free throw.”
Yet the science is conclusive: proper technique matters.
And slowly, Dr. Schwieterman says, the clinical community is adapting. “I am witnessing the medical profession doing just that – relearning how to capture a proper BP reading. This is a good thing to avoid over-prescribing medicine for normotensive individuals.”
To quantify just how much technique influences results, Midmark commissioned the CORRECT BP Study in 2021 – a multi-site investigation conducted by a principal investigator, a clinical data scientist, and an independent Clinical Research Organization.
The study took blood pressure readings at The Ohio State University in three scenarios:
- Traditional technique on a high table without proper support
- Correct technique, following all SPRINT guidelines
- he original, incorrect position repeated, with order randomized
The results were eye-opening.
“The CORRECT BP study investigators found, with extremely high confidence, that improper technique resulted in a 7 mm systolic and 4.5 mm diastolic error on the HIGH side,” he said.
Those numbers may appear small at first glance. But at scale?
“This level of error would result in about 40 million patients being wrongly diagnosed,” he said. That’s “more people than in the entire state of Texas.”
The consequences ripple far beyond incorrect prescriptions. When clinics must report their hypertension control rates to payors, faulty readings can hurt their reimbursement. “With a 7/4.5 drop in their numbers,” he explains, many providers would suddenly meet performance thresholds – “without changing anything in their therapeutic programs.”
In other words, better technique can improve both population health and financial outcomes.
Matching the rigor of other diagnostic tests
Why does BP accuracy lag behind other clinical measurements? The discrepancy puzzles Dr. Schwieterman.
“Most of your readers are likely familiar with the need to fast before a blood test or prep in some way for a procedure,” he said. These protocols exist for a reason: they ensure the results reflect reality.
Blood pressure should be no different.
“Patients need to avoid recent caffeine, empty their bladder, skip the cigarettes and avoid talking during the testing,” he said. Combined with proper positioning and a quiet rest period, these steps create a consistent and reliable baseline.
When half the population has high blood pressure and half does not, “the only way to know which is which, is to capture as accurate as possible measurements.”
Anything less risks overtreatment, expense, inconvenience – or dangerous undertreatment.
Exam room setup: The foundation of accuracy
Better BP measurement doesn’t fall solely on clinicians. The environment itself must support the right behaviors.
“There are so many things that need to be done at every encounter and often not enough time to do them,” he said. “So, it is essential that the setup and equipment make the job as efficient as possible.”
That means exam chairs that allow patients to rest their feet flat on the floor. Armrests positioned at heart level. Support behind the back. Equipment that prompts standardization instead of shortcuts.
“Setup and equipment” must make doing things the right way the easiest way.
Why BP is front and center in chronic disease prevention
The broader push for chronic disease management – including diabetes, kidney disease, cardiac health, and even cognitive function – has made BP accuracy even more essential.
“Even cognitive disorders have been found to be accelerated by elevated BP,” he said. Blood pressure’s influence touches nearly every system in the body.
“One reason BP is so prevalent as a quality measure among payors and quality supervisors is this one attribute of human physiology can significantly impact so many heavy hitting chronic conditions,” he added, including “heart attacks, strokes, diabetes, cognitive disorders, kidney function and peripheral vascular issues.”
Put simply: getting BP right helps prevent or delay a long list of complications.
“It is a blessing that blood pressure is both easy to measure and easy to treat, in most cases.”
A call to distributors and providers
For Dr. Schwieterman, the message to Repertoire’s audience of healthcare distributors and frontline providers is clear.
“There aren’t many aspects to patient care where one test can positively impact so many disorders,” he said. Treating osteoporosis strengthens bones. Treating thyroid disorders affects specific organs. But with blood pressure, “proper treatment positively impacts dozens of problematic disorders.”
This is why the stakes are so high – and why the opportunity is so great.
“That’s why proper blood pressure measurement is so essential when trying to achieve holistic and long-term outcomes,” he said.
Midmark’s Better BP® Program began with a simple but transformative realization: improving blood pressure accuracy required a fully integrated clinical process. The initiative is built on three pillars proven to reduce variation in blood pressure measurement: proper patient positioning, standardized automated BP capture, and seamless EMR connectivity. Together, these elements create a point-of-care ecosystem designed to generate more reliable readings, enhance workflow efficiency, and support better clinical outcomes.
According to Dr. Thomas Schwieterman, Vice President of Clinical Affairs and Chief Medical Officer at Midmark, the spark for the program came during a 2015–2016 product planning meeting. At the time, the SPRINT trial had just been published in The New England Journal of Medicine, offering clear evidence on how to achieve a true resting blood pressure. The study emphasized two critical factors: averaging multiple readings and positioning patients correctly. Midmark had just developed a new exam chair with support rails that aligned perfectly with all recommended positioning requirements.
When the team recognized they could also embed validated averaging protocols into their vital signs device, the vision crystallized. As COO at the time, Mike Walker put it, Midmark wasn’t just delivering equipment – “we’re providing accurate blood pressure.”