(26 days)
The Microlife Wrist Watch Blood Pressure Monitor, Model BP3AX1-4U with semiconductor pressure sensor is a device intended to measure the systolic and diastolic blood pressure and pulse rate of an adult individual by using a technique in which an inflatable cuff is wrapped around the wrist.
The device can be used in connection with your personal computer (PC) running the Microlife Blood Pressure Analyzer (BPA) software. The memory data can be transferred to the PC by connecting the monitor via cable with the PC.
The Microlife Wrist Watch Blood Pressure Monitor, Model BP3AX1-4U is designed to measure the systolic and diastolic blood pressure and pulse rate of an individual by using a technique in which an inflatable cuff is wrapped around the wrist. Our method to define systolic and diastolic pressures is similar to the auscultatory method but uses an electronic semiconductor pressure sensor rather than stethoscope and mercury manometer. The sensor converts tiny alteration in cuff pressure to electrical signals; by analyzing those signals to define the systolic, diastolic and calculating pulse rate is a well known technique in the market called the "oscillometric method". The device can be used in connection with your personal computer (PC) running the Microlife Blood Pressure Analyzer (BPA) software. The memory data can be transferred to the PC by connecting the monitor via cable with the PC.
The provided 510(k) summary for the Microlife Wrist Watch Blood Pressure Monitor, Model BP3AX1-4U, focuses on demonstrating substantial equivalence to a predicate device (Microlife Wrist Watch Blood Pressure Monitor, Model BP3AX1, K#040002) rather than presenting a standalone study with detailed acceptance criteria and performance metrics for the modified device. The key takeaway is that the clinical performance of the modified device is addressed by relying on the predicate device's compliance with the ANSI/AAMI SP10-2002 standard.
Here's an attempt to extract and synthesize the requested information based on the provided text, noting where information is not explicitly available for the modified device's clinical performance:
1. Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criteria | Reported Device Performance (Reference) |
|---|---|
| Compliance with ANSI/AAMI SP10-2002 "National Standard for Manual, Electronic or Automated Sphygmomanometers" for determining systolic and diastolic blood pressure and pulse rate (specifically, "All relevant sections were addressed and testing conducted"). | The predicate device (Microlife Wrist Watch Blood Pressure Monitor, Model BP3AX1) met all relevant requirements of this standard. The modified device (BP3AX1-4U) is stated to also meet these requirements as clinical testing results were not affected by the changes to the modified device (which was the addition of a PC-link function). |
| Electrical, Mechanical and Environmental Performance Requirements (as outlined in FDA November 1993 Draft "Reviewer Guidance for Premarket Notification Submissions", DCRND). | The Microlife Wrist Watch Automatic Blood Pressure Monitor, Model BP3AX1-4U met all relevant requirements of the conducted tests (Reliability Tests - Storage, Operating, Vibration, Drop, Life; EMC Test; PC-link software BPA Test). |
Note: The document explicitly states: "Repeat testing was not performed for the modified device, as clinical testing results were not affected by the changes to the modified device." This means the reported clinical performance refers to the predicate device's performance against the ANSI/AAMI SP10-2002 standard. Specific numerical performance metrics (e.g., mean difference, standard deviation) for blood pressure accuracy as per the AAMI standard are not provided in this summary for either the predicate or the modified device.
2. Sample Size Used for the Test Set and Data Provenance
- Sample Size for Clinical Performance (Predicate Device): Not explicitly stated in the provided text for the clinical study that proved compliance with ANSI/AAMI SP10-2002.
- Data Provenance: Not explicitly stated for any clinical study. The summary focuses on non-clinical and technical tests for the modified device, and refers to clinical testing performed on the predicate device.
3. Number of Experts Used to Establish Ground Truth for the Test Set and Their Qualifications
- For Clinical Performance (Predicate Device): Not specified in the provided text. The ANSI/AAMI SP10 standard typically involves comparison against mercury sphygmomanometry performed by trained observers, but the number and qualifications of these observers are not detailed here.
- For Non-Clinical Tests (Modified Device): No experts were involved in establishing ground truth for the non-clinical and technical tests (reliability, EMC, PC-link software).
4. Adjudication Method for the Test Set
- For Clinical Performance (Predicate Device): Not specified. Standard practice for AAMI SP10 validation involves specific procedures for comparing automated readings against auscultatory readings, often involving multiple observers, but the adjudication method (e.g., 2+1, 3+1) is not explicitly detailed.
- For Non-Clinical Tests (Modified Device): Not applicable. These tests are objective pass/fail based on engineering specifications.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was done, and the effect size of how much human readers improve with AI vs without AI assistance
- No such study was performed. This type of study is not relevant to a blood pressure monitor, which is a standalone measurement device, not an AI-assisted diagnostic tool for interpretation by human readers.
6. If a Standalone (i.e. algorithm only without human-in-the-loop performance) was done
- Yes, in essence. The blood pressure monitor itself is a standalone device that provides measurements via its internal algorithm. The "oscillometric method" is an algorithm. The clinical testing of the predicate device against the ANSI/AAMI SP10-2002 standard essentially represents a standalone performance evaluation of the device's algorithm against a recognized standard reference method (auscultatory measurement).
7. The Type of Ground Truth Used
- For Clinical Performance (Predicate Device): The ground truth for blood pressure measurement against the ANSI/AAMI SP10-2002 standard would typically be auscultatory blood pressure measurements performed by trained observers using mercury sphygmomanometers. This is generally considered an "expert consensus" or "reference standard" method in this context.
- For Non-Clinical Tests (Modified Device): The ground truths were engineering specifications and functional requirements (e.g., successful data transfer for PC-link).
8. The Sample Size for the Training Set
- Not applicable / Not specified. The device uses the "oscillometric method," which is a well-known, established algorithm, not typically "trained" in the sense of modern machine learning models with large datasets. If there were any algorithmic refinements based on data, the size of that data is not mentioned in the summary.
9. How the Ground Truth for the Training Set Was Established
- Not applicable / Not specified. As noted above, the "oscillometric method" is a long-established technique. The summary does not describe a machine learning training process.
§ 870.1130 Noninvasive blood pressure measurement system.
(a)
Identification. A noninvasive blood pressure measurement system is a device that provides a signal from which systolic, diastolic, mean, or any combination of the three pressures can be derived through the use of tranducers placed on the surface of the body.(b)
Classification. Class II (performance standards).