(98 days)
The Arm Blood Pressure Monitor is intended to measure the systolic and diastolic blood pressure, as well as the pulse rate of adult person via non-invasive oscillometric technique in which an inflatable CUFF is wrapped around the upper arm at medical facilities or at home.
Arm blood pressure monitor, models(models ARM-30H, ARM-30J, ARM-30K and AOJ-90B), are designed as a battery driven automatic no-invasive blood pressure monitor. It can automatically complete the inflation, deflation and measurement, which can measure systolic and diastolic blood pressure as well as the pulse rate of adult person at upper arm within its claimed range and accuracy via the oscillometric technique. The result will be displayed in the international unit mmHg or Kpa. All the models included in this submission follow the similar software, same measurement principle and same specifications. All the models can be used with one cuff size 2242 cm (8.616.5 inches). AOJ90B has extra 4G network except for other models.
Here's an analysis of the provided FDA 510(k) clearance letter to extract information on acceptance criteria and the study proving device performance:
Summary of Device and Context:
The submission K250116 concerns several models of Arm Blood Pressure Monitors (ARM-30H, ARM-30J, ARM-30K, ARM-90B) manufactured by Shenzhen AOJ Medical Technology Co., Ltd. These devices are intended for non-invasive oscillometric measurement of systolic and diastolic blood pressure and pulse rate in adults, for both medical facilities and home use. The predicate device is the Arm Blood Pressure Monitor, model AOJ-30B (K222125).
1. Table of Acceptance Criteria and Reported Device Performance
| Parameter | Acceptance Criteria (Predicate) | Reported Device Performance (Proposed Device) | Study Type Supporting Performance |
|---|---|---|---|
| Blood Pressure Accuracy | ± 3 mmHg | ± 3 mmHg | Clinical |
| Heart Rate Accuracy | ± 5% | ± 5% | Clinical |
| Biocompatibility | Cytotoxicity, Sensitization, Irritation (ISO 10993-1, 10993-5, 10993-10) | Cytotoxicity, Sensitization, Irritation (ISO 10993-1, 10993-5, 10993-10, 10993-23) | Non-clinical (Bench) |
| Electrical Safety | IEC 60601-1, IEC 60601-1-11, ISO 80601-2-30 | IEC 60601-1, IEC 60601-1-11, ISO 80601-2-30 | Non-clinical (Bench) |
| EMC Compliance | IEC 60601-1-2 | IEC 60601-1-2 | Non-clinical (Bench) |
| Wireless Coexistence | Not explicitly stated for predicate in table, but 4G for ARM-90B. | ANSI C63.27:2017, AAMI TIR69:2017 risk management, FDA Guidance for RF Wireless Technology in Medical Devices. | Non-clinical (Bench) |
| Clinical Performance | Mean error and standard deviation of differences for systolic/diastolic pressure not over limits of ISO 81060-2. | Mean error and standard deviation of differences for systolic/diastolic pressure not over limits of ISO 81060-2. | Clinical |
2. Sample Size and Data Provenance for Test Set (Clinical Studies)
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Clinical Study for ARM-90B:
- Sample Size: 100 adult subjects (61 females, 39 males)
- Age Range: 19 to 77 years
- Data Provenance: Not explicitly stated (e.g., country of origin). Since Shenzhen AOJ Medical Technology Co., Ltd. is based in China, it's highly probable the study was conducted there, but this is not confirmed in the provided text. The study method was prospective, as subjects were enrolled for the purpose of the study.
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Clinical Study for ARM-30H:
- Sample Size: 100 adult subjects (54 females, 46 males)
- Age Range: 18 to 80 years
- Data Provenance: Not explicitly stated. Likely prospective, similar to ARM-90B.
3. Number of Experts and Qualifications for Ground Truth
The document does not provide information on the number of experts used to establish ground truth or their specific qualifications (e.g., "radiologist with 10 years of experience"). For blood pressure monitor clinical studies, ground truth is typically established by trained technicians or clinicians using validated reference devices, but the specific details are not present.
4. Adjudication Method for Test Set
The document does not specify any adjudication method (e.g., 2+1, 3+1). For blood pressure studies following ISO 81060-2, the ground truth measurements are usually taken by trained observers using mercury sphygmomanometers or other validated reference methods. The standard itself outlines the procedures for taking these measurements, which inherently involves multiple measurements and comparisons, but not necessarily a formal adjudication process in the sense of resolving conflicting interpretations of images or complex diagnostic results. The "Same Arm Sequential Method" was chosen for both studies, indicating a direct comparison of the device's readings against reference readings on the same arm of the subject.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
No MRMC comparative effectiveness study was done.
This type of study is typically relevant for interpretative devices (e.g., AI in radiology) where human readers are making diagnoses. For a blood pressure monitor, the device provides a direct measurement, not an interpretation that a human would then refine. The clinical studies directly evaluate the device's accuracy against a recognized reference standard.
6. Standalone (Algorithm Only) Performance Study
Yes, a standalone performance study was done for the device. The clinical studies performed according to ISO 81060-2 directly assess the performance of the device itself (the algorithm within the device) against a reference standard without human intervention in interpreting the device's output. The device is the algorithm in this context, automatically performing inflation, deflation, and measurement.
7. Type of Ground Truth Used
The ground truth used for the clinical studies was established by comparison with a reference method defined by ISO 81060-2. This standard outlines precise procedures for obtaining reference blood pressure measurements (typically using a mercury sphygmomanometer or other validated reference devices operated by trained observers) against which the automated device's readings are compared. The criteria state "mean error and standard deviation of differences for systolic, diastolic pressure is not over the limits of ISO 81060-2," which implies the ground truth is based on reference measurements adhering to this international standard.
8. Sample Size for the Training Set
The document does not provide information on the sample size for the training set.
510(k) submissions typically focus on the performance of the final device, not the details of its development or training data for its internal algorithms, unless the device explicitly uses machine learning algorithms that are updated or adapt. For a standard oscillometric blood pressure monitor, the algorithm is generally fixed and designed based on established physiological principles and extensive validation, rather than being "trained" on a dataset in the modern sense of machine learning.
9. How the Ground Truth for the Training Set Was Established
As with the training set sample size, the document does not provide information on how the ground truth for any potential training set was established. Given the nature of a blood pressure monitor, the "training" (if it occurs in a machine learning context) would likely involve extensive data collection with reference ground truth from validated sphygmomanometers, similar to the clinical validation studies, but specifically for internal algorithm development and refinement. However, this is speculative as the document does not detail the development 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).