(192 days)
WS20A is a pulse oximeter indicated for use in measuring, displaying, storing and transmitting functional oxygen saturation of arterial hemoglobin (SpO2) and pulse rate for patients(≥10 years old, ≥30kg). It is designed for finger circumference more than 33mm. It is intended for spot-check, continuous data collection, recording and transmitting, not continuous monitoring. It can be used in sleep labs, long-term care, hospitals and home.
Pulse Oximeter WS20A is an internally powered pulse oximeter. The main functions of the devices include hemoglobin oxygen saturation (SpO2), pulse rate (PR) measurements and Pulse amplitude index (PAI), data storage and transmission. Place one fingertip into the sensor and the oxygen saturation (SpO2), pulse rate (PR) measurements and pulse amplitude index (PAI) will appear on the display. The device is intended to be applied to adult and pediatric patients in sleep labs, long-term care, hospital and home care environment. The subject device is composed of the following components to achieve the above detection process: power supply module, detector and emitter, signal collection and process module (MCU), TFT display screen and Bluetooth module.
The provided text describes the 510(k) summary for the Hunan Accurate Bio-Medical Technology Co., Ltd.'s Pulse Oximeter (WS20A). While it details the device, its intended use, and comparison to a predicate device, it does not contain a specific table of acceptance criteria with reported device performance in the format of typical medical device performance claims (e.g., sensitivity, specificity, accuracy for an AI/diagnostic device).
Instead, the performance criteria for this pulse oximeter are related to its accuracy in measuring SpO2 and Pulse Rate against a reference standard (CO-Oximetry). The acceptance criteria for pulse oximeters are typically defined by recognized standards such as ISO 80601-2-61, which specifies the accuracy requirements (e.g., ARMS value).
Based on the provided text, here's an attempt to extract the relevant information and present it as requested.
Overview of Device Performance and Study
The Pulse Oximeter (WS20A) underwent clinical studies to verify its accuracy in measuring functional oxygen saturation of arterial hemoglobin (SpO2) against arterial blood CO-Oximetry, in accordance with ISO 80601-2-61:2017 and FDA guidance for Pulse Oximeters - Premarket Notification Submissions.
1. Table of Acceptance Criteria and Reported Device Performance
For pulse oximeters, the key performance metric for SpO2 accuracy is typically the Accuracy Root Mean Square (ARMS) value when compared to a reference method (CO-Oximetry). The acceptance criterion is generally that the ARMS value should be within a specified limit, commonly ± 3% for 70-100% SpO2 range as per ISO 80601-2-61.
| Performance Metric | Acceptance Criteria (ARMS for SpO2, 70-100% range) | Reported Device Performance (ARMS for SpO2, 70-100% range) |
|---|---|---|
| SpO2 Accuracy | $\leq \pm 3$% (derived from ISO 80601-2-61) | Adult Patients: |
- All subjects: 1.81%
- Female subjects: 1.80%
- Male subjects: 1.83%
- Light-skinned: 1.78%
- Dark-skinned: 1.91%
Pediatric Patients:
- 10 female subjects: 1.80%
- Light-skinned: 1.81%
- Dark-skinned: 1.74% |
| PR Accuracy (bpm) | ± 3bpm (as per predicate device spec) | Not explicitly reported from clinical study for WS20A. The 510(k) submission document for WS20A lists its PR accuracy as ± 3 bpm, which aligns with its own stated specifications and is compared to a similar specification for the predicate. |
Note: The acceptance criteria for ARMS are not explicitly stated as a number in the provided text but are inferred from common regulatory expectations for pulse oximeters based on the ISO standard cited.
2. Sample Size Used for the Test Set and Data Provenance
- Adult Patients: 13 healthy adult subjects. 315 data sets (SpO2 vs SaO2) were obtained.
- Pediatric Patients: 10 healthy female subjects. 243 data sets (SpO2 vs SaO2) were obtained. (Note: The description states "healthy female subjects, aged 22-30" for 'pediatric patients' which seems to be a typo given the 'pediatric' labeling and the age range overlaps with 'adult'. Assuming this refers to subjects representing a pediatric patient population as defined by the study design, or a mislabeling of the subject group based on physical characteristics matching the pediatric profile for device testing.)
- Data Provenance: The document does not specify the country of origin of the data. The studies were described as "clinical studies" and appear to be prospective in nature, as they involved actively obtaining data sets from healthy subjects under stationary (non-motion) conditions through controlled desaturation.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
The ground truth for pulse oximetry accuracy studies is established through arterial blood CO-Oximetry, which is a direct invasive measurement of arterial oxygen saturation (SaO2). This is a gold standard laboratory method, not typically established by physician experts in the same way as image interpretation. The text does not mention the use of experts for ground truth establishment; rather, it relies on the direct physiological measurement.
4. Adjudication Method for the Test Set
Not applicable. Ground truth for oxygen saturation in these studies is derived from direct physiological measurement (CO-Oximetry) rather than expert consensus requiring adjudication.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance
Not applicable. This device is a pulse oximeter for direct physiological measurement, not an AI-assisted diagnostic imaging device requiring human reader interpretation for a comparative effectiveness study.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) was done
Yes, the performance presented (ARMS values) represents the standalone accuracy of the pulse oximeter device algorithm in measuring SpO2 against the CO-Oximetry reference. While a human uses the device, the accuracy is derived from the device's measurement capabilities.
7. The Type of Ground Truth Used
The ground truth used was arterial blood CO-Oximetry (SaO2), which is a gold standard for measuring oxygen saturation in the blood. This is a direct physiological measurement, not expert consensus or pathology.
8. The Sample Size for the Training Set
The document describes clinical studies conducted to verify the accuracy of the proposed device. It does not explicitly mention a "training set" for an algorithm in the sense of machine learning. The data described (from 13 adult and 10 "pediatric" subjects) appears to be the test/validation set used to demonstrate the device's accuracy. For traditional medical devices like pulse oximeters, the core measurement principles are physics-based, not reliant on machine learning models that require distinct training sets. Any internal calibration or algorithm development would typically occur during the R&D phase, prior to these described validation studies, and the size of data used for such internal development is not generally disclosed in 510(k) summaries unless it's a novel AI/ML device.
9. How the Ground Truth for the Training Set was Established
Not applicable, as a distinct "training set" in the context of an AI/ML device is not described for this traditional pulse oximeter. If there were internal algorithm development or calibration, the ground truth would likely have been established using similar reference methods (CO-Oximetry) in controlled lab settings.
§ 870.2700 Oximeter.
(a)
Identification. An oximeter is a device used to transmit radiation at a known wavelength(s) through blood and to measure the blood oxygen saturation based on the amount of reflected or scattered radiation. It may be used alone or in conjunction with a fiberoptic oximeter catheter.(b)
Classification. Class II (performance standards).