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Dyshemoglobins and Pulse Oximetry: How COHb and MetHb Influence Measurement Accuracy   Pulse oximetry has become central to physiological monitoring across wearables, medical devices, and clinical research studies. Yet even the most advanced sensor architectures face fundamental challenges when hemoglobin exists in altered forms—known as dyshemoglobins . Carboxyhemoglobin (COHb) and methemoglobin (MetHb) change light absorption in ways that directly influence SpO₂ readings an

When planning a clinical research study intended to support an FDA submission , sponsors often encounter terms such as multi-site, multi-investigator , and single-site, multiple-location . While these models may appear operationally similar, they differ in oversight structure, execution, and how evidence is evaluated by the FDA—particularly for cuffless blood pressure devices . Understanding these distinctions is essential for aligning trial design with FDA expectations and w

Why ISO 81060-2 Matters for Accurate Blood Pressure Monitoring   Non-invasive blood pressure devices must demonstrate dependable performance before developers can advance toward FDA or CE mark submissions. ISO 81060-2  “Non-invasive sphygmomanometers — Part 2: Clinical investigation of intermittent automated measurement type ” sets a clear bar for clinical validation—defining study methods, reference comparisons, subject distribution, cuff/arm-size coverage, and prespecified

Accurate oxygen saturation measurement is foundational for modern physiological monitoring, especially for developers of pulse oximeters, wearables, and multiparameter platforms. Yet many devices fail to achieve regulatory expectations because their performance is never tested across the full range of oxygen saturation levels humans experience.  Controlled desaturation studies fill this gap, ensuring claims reflect real-world performance. These studies intentionally and safel

Transparent clinical operations have become a defining differentiator for high-performing contract research organizations. Yet many medical device and wearable developers still encounter opaque decision-making, limited protocol visibility, and communication gaps that slow execution and create unnecessary regulatory friction. The result is predictable: CRO risk mitigation becomes reactive instead of proactive , and promising technologies reach the FDA or CE mark later than the

Engineering leaders developing physiological monitoring devices often encounter references to “arterial line measurements” in validation standards and technical literature. Although arterial lines are invasive and placed in clinical environments, the data they generate is central to how the industry defines accuracy for non-invasive technologies.  This article explains what an arterial line is, why its measurements are considered a benchmark, and how arterial line data is use

Engineering Reliability: What CTOs Need to Know About Regulatory-Grade Physiological Monitoring Validation   CTOs in medical-device startups face an engineering challenge that extends far beyond hardware and firmware. The success of a physiological monitoring product—whether a pulse oximeter, blood pressure monitor, or wearable sensing platform—depends on rigorous clinical research studies capable of supporting FDA and CE mark submissions. The gap between early engineering va

How PRL Ensures Data Integrity in Physiological Monitoring Research   For CTOs and technical leaders in MedTech, data integrity is not a paperwork detail—it is the backbone of regulator-ready evidence. Whether your device requires pulse oximetry testing during controlled desaturation in a hypoxia lab, multi-parameter wearables validation, or multi-site clinical research studies, every data point must be defensible. ALCOA+ provides the industry-standard framework for achieving

Introduction: Inclusion Begins with Ethical Engagement   In clinical research, the term “vulnerable populations” describes individuals who may be at risk of coercion, manipulation, or harm due to limited autonomy, health literacy, socioeconomic disadvantage, or institutional dependence. Examples include individuals with cognitive limitations, students or employees under authority, people with limited language proficiency, or those experiencing social or economic marginalizat

Introduction: Verification Defines Trust in Pulse Oximetry Pulse oximeters are among the most widely used physiological monitoring devices—found in hospitals worldwide. Yet, behind every reliable SpO₂ reading lies a complex scientific process: verification against reference standards . Pulse oximeter verification studies (or pivotal studies) confirm how closely a device’s functional oxygen saturation (SpO₂) values align with the true arterial oxygen saturation (SaO₂), measure

Introduction: The Foundation of Reliable Oxygenation Research   Controlled desaturation studies are central to validating  pulse oximeters . These studies, performed in specialized hypoxia laboratories  such as PRL, safely lower arterial oxygen saturation (SaO₂) to predefined plateaus, typically from %100 to 70% SaO₂, generating reference data used to calibrate or verify pulse oximeters.  At the core of this process lies one indispensable element: accurate blood gas analysis

Introduction: Why Respiratory Rate Matters in Physiological Monitoring   Respiratory rate (RR) is a vital indicator of physiological stability—often the first parameter to shift in response to metabolic stress, infection, or hypoxia. Yet, continuous and unobtrusive respiratory monitoring remains challenging outside of controlled environments.  With the rise of wearable and optical sensing technologies, electrocardiography (ECG) and photoplethysmography (PPG) have emerged as

Introduction: The Importance of Clarity in Blood Pressure Device and Software Classification   As wearable technology advances, more devices are integrating blood pressure features—from clinical-grade monitors to smartwatches that “notify” users of potential changes. But not all blood pressure devices are created—or regulated—the same.  Understanding the difference between a blood pressure measurement device (FDA product code DXN) and a hypertension machine learning-based no

Why Verification Matters in BP Devices   Blood pressure (BP) measurement is a foundation of cardiovascular care. But not all BP devices are created equal — increasingly, clinicians and patients recognize that a blood pressure reading is only useful if it’s accurate.  To address market confusion around which BP monitors are reliable, the American Medical Association (AMA) introduced the Validated Device Listing (VDL) . The VDL is a free resource that helps clinicians, health

The Hidden Measurement Problem Behind COVID-19 Hypoxia   During the height of the COVID-19 pandemic, clinicians encountered a puzzling trend: individuals with dangerously low arterial oxygen levels often appeared clinically stable and comfortable. While “silent” or “happy” hypoxia drew headlines, an equally critical issue— occult hypoxemia —posed a more subtle risk.  Occult hypoxemia  occurs when pulse oximetry readings overestimate true arterial oxygen saturation (SaO₂), mas

The Growing Importance of Precision in Oxygen Monitoring   From hospital wards to fitness wearables, pulse oximeters  have become indispensable tools for noninvasively measuring blood oxygen saturation (SpO₂). Yet the accuracy of these devices, particularly across diverse skin tones and environmental conditions, has come under scrutiny in recent years.  As regulatory bodies and clinical researchers call for more inclusive and transparent validation, the need for a specialized

A Persistent Problem Hidden in Plain Sight   For decades, pulse oximetry has served as a cornerstone of clinical monitoring—offering a quick, noninvasive estimate of blood oxygen saturation (SpO₂). Yet, the COVID-19 pandemic exposed a long-standing and underappreciated flaw: pulse oximeters can overestimate oxygen levels in individuals with darker skin pigmentation .  Inaccurate SpO₂ readings may mask hypoxemia , delay treatment decisions, and contribute to existing health di

In clinical research for medical devices and wearable technologies, data quality is everything . Regulatory clearance depends not just on whether a study was conducted, but on whether the data generated is regulator-ready, reproducible, and scientifically defensible . Yet not all Service Providers (formally known as Clinical Research Organizations (CROs)) bring the same level of expertise, infrastructure, or dedicated staff to ensure that outcome.  Sponsors sometimes face a d

Introduction: A New Standard on the Horizon   On January 6, 2025 , the FDA released a draft guidance  titled Pulse Oximeters for Medical Purposes: Non-Clinical and Clinical Performance Testing, Labeling, and Premarket Submission Recommendations . This draft guidance updates and expands upon earlier 510(k) and performance expectations for pulse oximeters, placing renewed emphasis on accuracy across skin pigmentation  and non-disparate performance .   Crucially, the draft does

For medical device and wearable technology developers, the success of a clinical research study often hinges on one factor: the quality...