(100 days)
The Shenzhen Belter Health Measurement and Analysis Technology Co., Ltd. Body Fat Scale SF-371 measures body weight, and estimates body fat, body water, body muscle mass and body bone mass using BIA (bioelectrical impedance analysis). The device is intended to be used by generally healthy people (from age 16 to age 80) who are not ill, feverish, have a chronic or acute disease, or a condition that affects the level of hydration such as pregnancy.
The patient steps on the scale device, where four electrodes are located. The patient must step on the electrodes with bare feet, with normal moisture. Through harmless current stimulation of 500 µA, at 50 kHz, the Shenzhen Belter Health Measurement and Analysis Technology Co., Ltd. Body Fat Scale calculates the body fat percentage. This calculation is done via the Bioelectrical Impedance Method. The current is passed through the body and the impedance of the body determines the body fat. The calculation is based upon electrical impedance, height, weight, age, and gender. The calculation is performed via internal software, which uses the variables programmed in by the user. There are elements of this process that can produce erroneous readings, such as dry feet or improper-programmed data. The User's Manual defines items which could cause erroneous readings.
Here's an analysis of the provided text regarding the acceptance criteria and study for the Body Fat Scale, Model SF-371 (K122976):
The provided 510(k) summary (K122976) for the Shenzhen Belter Health Measurement and Analysis Technology Co., Ltd. Body Fat Scale, Model SF-371, is quite limited in detail regarding specific acceptance criteria and the clinical study. It states that "Clinical testing was used to validate the effectiveness and accuracy of the device. All test results were satisfactory." However, it does not provide specific metrics or outcomes from this clinical testing.
Therefore, much of the requested information cannot be directly extracted from the provided document. I will present what is available, and for missing information, I will explicitly state that it is not provided.
1. Table of Acceptance Criteria and Reported Device Performance
The 510(k) summary states that "Clinical testing was used to validate the effectiveness and accuracy of the device. All test results were satisfactory." However, no specific acceptance criteria or quantitative performance metrics (e.g., accuracy percentages, standard deviations, correlation coefficients) are provided in the document.
| Acceptance Criteria | Reported Device Performance |
|---|---|
| Not specified | "All test results were satisfactory." |
| Not specified | No quantitative performance data provided. |
2. Sample Size Used for the Test Set and Data Provenance
The document states that "Clinical testing was used to validate the effectiveness and accuracy of the device," but it does not specify the sample size used for this test set.
Data Provenance: The document does not explicitly state the country of origin for the clinical testing data. Given that the submitting company is based in Shenzhen, China, it is plausible the testing was conducted locally, but this is not confirmed. It also does not specify whether the data was retrospective or prospective.
3. Number of Experts Used to Establish Ground Truth and Their Qualifications
The 510(k) summary does not provide any information regarding the number of experts used, their qualifications, or how ground truth was established for the clinical testing.
4. Adjudication Method for the Test Set
The document does not specify any adjudication method used for the clinical testing.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
The document does not mention any MRMC comparative effectiveness study involving human readers or AI assistance. The device is a "Body Fat Scale," which is a direct measurement device rather than an interpretive imaging or diagnostic system that would typically involve MRMC studies.
6. Standalone (Algorithm Only) Performance
The device itself is a standalone algorithm for calculating body composition based on bioelectrical impedance. The statement "Clinical testing was used to validate the effectiveness and accuracy of the device" implicitly refers to the standalone performance of the device's calculations. However, no specific performance metrics are provided.
7. Type of Ground Truth Used
The document does not specify the type of ground truth used for validation. For body fat scales, common ground truth methods include DEXA (Dual-energy X-ray absorptiometry), hydrostatic weighing, or air displacement plethysmography, but none of these are mentioned.
8. Sample Size for the Training Set
The document does not provide any information regarding a training set sample size. This type of device relies on internal algorithms based on established bioelectrical impedance principles and user-programmed variables, rather than a deep learning model requiring a distinct "training set" in the modern AI sense.
9. How Ground Truth for the Training Set Was Established
Since no training set is described in the context of an AI/machine learning model, this information is not applicable and therefore not provided in the document. The device's calculations are based on bioelectrical impedance method, using electrical impedance, height, weight, age, and gender, likely derived from scientific literature and established physiological models rather than a specific "training set" with ground truth in the typical AI development paradigm.
§ 870.2770 Impedance plethysmograph.
(a)
Identification. An impedance plethysmograph is a device used to estimate peripheral blood flow by measuring electrical impedance changes in a region of the body such as the arms and legs.(b)
Classification. Class II (special controls). The device, when it is a body composition analyzer which is not intended to diagnose or treat any medical condition, is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in § 870.9.