The Yamato ClockMINI and ClockNAVI Body Fat Monitors are intended for use in the estimation of body fat percent in users between the ages of 10 and 80 years old.

Device Description

The Yamato ClockMINI Body Fat Monitor -- DF301 (ClockMINI) is an over-the-counter body composition analyzer and clock that uses Bioelectrical Impedance Analysis (BIA) to estimate body fat percent by measuring the electric resistance sensed when a 50kHz/500 µ A current is passed through the body. From this measurement the device uses an algorithm to display an estimate of body fat percent. In addition, the ClockMINI classifies the body fat percent into one of four categories: low, average, high, and very high.

The Yamato ClockNAVI Body Fat Monitor - DF311 (ClockNAVI) is an over-the-counter body composition analyzer and clock that uses Bioelectrical Impedance Analysis (BIA) to measure body fat percent by measuring the electric resistance sensed when a 50kHz/500 µ A current is passed through the body. From this measurement the device uses an algorithm to display an estimate of body fat percent and a classification of obesity level. The device also calculates Body Mass Index (BMI) from data input by the user and displays an obesity level classification based on the calculated BMI.

AI/ML Overview

Here's an analysis of the acceptance criteria and study detailed in the provided text:

1. Table of Acceptance Criteria and Reported Device Performance

Acceptance Criteria (Implied)	Reported Device Performance
Device provides accurate estimation of body fat percentage.	The average difference between the Yamato devices and the Under Water Weighing (UWW) method was: - Males: 0.1% - Females: -0.2%
Device shows minimal variability compared to the gold standard (UWW).	The standard deviation of the difference between the Yamato devices and UWW was between 3.2% and 3.3% for both males and females. The document states these numbers are "quite small" when considering the variability associated with both methods (UWW and BIA).
Device is suitable for the intended user population (age 10-80).	The devices were tested against the UWW method, and the results are presented for male and female populations, supporting the stated age range by not identifying any age-related performance issues. The primary indication for use for the Yamato devices is the estimation of body fat percent in users between the ages of 10 and 80 years old, which is consistent with the predicate device.
The technological characteristics of the device align with the predicate device (Omron HBF-306 Body Fat Analyzer).	The devices are equivalent in: - Method for estimating body fat percent (BIA) - Calculation for Body Mass Index (BMI) - Current and Frequency specifications (50kHz/500µA) - Route of current through the body - Data input (height, weight, age, gender) - Output parameters (BMI (ClockNAVI only), Body Fat%)

2. Sample Size Used for the Test Set and Data Provenance

Sample Size: 149 subjects (51 males and 98 females).
Data Provenance: The document does not explicitly state the country of origin. It mentions a "Yamato study," which implies it was conducted by the manufacturer or a third party on their behalf. The data is retrospective in the sense that the study was conducted and then reported for regulatory submission.

3. Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications

This information is not applicable in the traditional sense of expert review for image-based diagnostics. The ground truth method used was an objective measurement: Under Water Weighing (UWW), which is considered a gold standard for body composition analysis. Therefore, no "experts" were used for subjective assessment; the UWW method itself provides the ground truth.

4. Adjudication Method for the Test Set

None. Since the ground truth was an objective measurement (UWW), there was no need for expert adjudication. The comparison was directly between the device's output and the UWW measurement.

5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study

No. An MRMC study was not performed. This type of study is more relevant for diagnostic devices where human readers interpret medical images or data. The Yamato devices are standalone body fat monitors, and the performance study was a direct comparison to an objective gold standard, not an assessment of human interpretation with or without AI assistance.

6. Standalone Performance Study

Yes. The described study is a standalone performance study. It directly assessed the algorithm's performance (as embodied by the Yamato ClockMINI and ClockNAVI devices) by comparing its body fat percentage estimates against the Under Water Weighing (UWW) method, which served as the ground truth. There was no human-in-the-loop component in this particular performance assessment.

7. Type of Ground Truth Used

Objective Measurement (Gold Standard): Under Water Weighing (UWW).

8. Sample Size for the Training Set

Not explicitly stated/Not applicable for this type of device submission. The document describes a performance evaluation of the final device/algorithm, not the development or training of the algorithm itself. For a 510(k) submission for a device like this, the focus is typically on demonstrating substantial equivalence to a predicate device and showing that the final product performs as intended. The details of the algorithm's internal training data are not typically required for this type of submission.

9. How the Ground Truth for the Training Set Was Established

Not explicitly stated/Not applicable for this device submission. As mentioned above, the submission focuses on the performance of the final device. The document does not provide details on the development or training of the Bioelectrical Impedance Analysis (BIA) algorithms used in the Yamato devices, nor how any potential "training" ground truth would have been established for this internal process. The BIA method is a well-established scientific principle with algorithms developed over time, not necessarily a machine learning model that undergoes a distinct "training set" process for each new device.

Summary

{0}------------------------------------------------

9. 510(k) Summary

FEB 2 4 2003

510(k) SUMMARY YAMATO ClockMINI and ClockNAVI BODY FAT MONITORS

SUBMITTER INFORMATION

Company name / address: Enscicon Corporation 518 17th Street Suite 1350 Denver, CO 80202

Contact name / numbers:

Clay Anselmo Phone: 800-341-4255 Fax: 303-832-6700

Date summary prepared:

October 22, 2002

Body Fat Analyzer

DEVICE IDENTIFICATION

Trade names:

Yamato ClockMINI Body Fat Monitor, DF301 Yamato ClockNAVI Body Fat Monitor, DF311

Common name:

Classification name:

Impedance Plethysmograph

Omron HBF-306 Body Fat Analyzer

PREDICATE DEVICE

Trade name:

510(k) number:

K011652

DEVICE DESCRIPTION

{1}------------------------------------------------

INDICATIONS FOR USE

The Yamato ClockMINI and ClockNAVI Body Fat Monitors are intended for use in the estimation of body fat percent in users between the ages of 10 and 80 years old.

TECHNOLOGICAL CHARACTERISTICS COMPARISON

Both of the Yamato devices and the Omron device are battery powered (2 "AAA" batteries) and pass a small electrical current (~500µA, 50kHz) through the hands, arms, and upper torso of the user for the purpose of calculating the bio-electrical impedance of the user. This method is commonly referred to as bio-electrical impedance analysis (BIA.)

The primary indication for use for the Yamato devices and the Omron device is the estimation of body fat percent. The intended user group for all of the devices for normal subjects is 10 to 80 vears. (The Omron device has an "athlete" mode that is not present in the Yamato devices.) The technological characteristics for all the devices are equivalent including the method for estimating body fat percent and the method for calculating body mass index (BMI).

The following primary characteristics of the two Yamato devices are equivalent to the Omron device.

Method for estimating body fat percent (BIA)
. Calculation for Body Mass Index (BMI)
Current and Frequency specifications
Route of current through the body .
Data input (height, weight, age, gender) .
Output parameters (BMI (ClockNAVI only), Body Fat%) .

PERFORMANCE DATA

To show acceptable performance of the Yamato ClockMINI and ClockNAVI devices for estimating body fat percentage, the devices were compared in a Yamato study against the under water weighing (UWW) method. Fifty-one males and 98 females had their body fat percentages estimated by both methods. The two methods provided very similar results overall. In both the male and female populations, the average difference between the Yamato device and the UWW method was extremely small (0.1% m, and -0.2% f) and the standard deviation of the difference was between 3.2% and 3.3%. When considering the variability associated with both methods, including measurement of residual volume in the lung, unpredictability of body water, and the estimation of intestinal tract volume, these numbers are quite small.

CONCLUSION

The Yamato ClockMINI and ClockNAVI Body Fat Monitors are substantially equivalent to the Omron HBF-306 Body Fat Analyzer.

{2}------------------------------------------------

Image /page/2/Picture/1 description: The image shows the logo for the U.S. Department of Health & Human Services. The logo features a stylized eagle with three lines representing its body and wings. The words "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" are arranged in a circular pattern around the eagle.

Food and Drug Administration 9200 Corporate Boulevard Rockville MD 20850

Yamato Corporation c/o Mr. Clay Anselmo Submission Correspondent Enscicon Corporation 518 17th Street Suite 1350 DENVER CO 80202

FEB 2 4 2003

Re: K023942

Trade/Device Name: Yamato ClockMINI Body Fat Monitor, DF301; and Yamato ClockNAVI Body Fat Monitor, DF311 Regulation Number: 21 CFR §870.2770 Regulation Name: Impedance plethysmograph Regulatory Class: II Product Code: 74 MNW Dated: November 18, 2002 Received: November 26, 2002

Dear Mr. Anselmo:

We have reviewed your Section 510(k) premarket notification of intent to market the device referenced above and have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Device Amendments, or to devices that have been reclassified in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (Act) that do not require approval of a premarket approval application (PMA). You may, therefore, market the device, subject to the general controls provisions of the Act. The general controls provisions of the Act include requirements for annual registration, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration.

If your device is classified (see above) into either class II (Special Controls) or class III (PMA), it may be subject to additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 898. In addition, FDA may publish further announcements concerning your device in the Federal Register.

Please be advised that FDA's issuance of a substantial equivalence determination does not mean that FDA has made a determination that your device complies with other requirements of the Act or any Federal statutes and regulations administered by other Federal agencies. You must comply with all the Act's requirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Part 801); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820); and if applicable, the electronic product radiation control provisions (sections 531-542 of the Act); 21 CFR 1000-1050.

{3}------------------------------------------------

This letter will allow you to begin marketing your device as described in your Section 510(k) premarket notification. The FDA finding of substantial equivalence of your device to a legally marketed predicate device results in a classification for your device and thus, permits your device to proceed to the market.

If you desire specific advice for your device on our labeling regulation (21 CFR Part 801), please contact the Office of Compliance at one of the following numbers, based on the regulation number at the top of the letter:

8xx.1xxx	(301) 594-4591
876.2xxx, 3xxx, 4xxx, 5xxx	(301) 594-4616
884.2xxx, 3xxx, 4xxx, 5xxx, 6xxx	(301) 594-4616
892.2xxx, 3xxx, 4xxx, 5xxx	(301) 594-4654
Other	(301) 594-4692

Additionally, for questions on the promotion and advertising of your device, please contact the Office of Compliance at (301) 594-4639. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21CFR Part 807.97) you may obtain. Other general information on your responsibilities under the Act may be obtained from the Division of Small Manufacturers. International and Consumer Assistance at its toll-free number (800) 638-2041 or (301) 443-6597 or at its Internet address http://www.fda.gov/cdrh/dsma/dsmamain.html.

Sincerely vours.

Nancy C. brogdon

Nancy C. Brogdon Director, Division of Reproductive, Abdominal and Radiological Devices Office of Device Evaluation Center for Devices and Radiological Health

Enclosure

Page 2

{4}------------------------------------------------

Page ___ of ___

510(k) Number (if known):	K023942
Device Name:	Yamato ClockMINI (DF301)Yamato ClockNAVI (DF311)

Indications for Use:

The Yamato ClockMINI and ClockNAVI Body Fat Monitors are intended for use in the estimation of body fat percent in users between the ages of 10 and 80 years old.

PLEASE DO NOT WRITE BELOW THIS LINE-CONTINUE ON ANOTHER PAGE OF NEEDED)

Concurrence of CDRH, Office of Device Evaluation (ODE)

David A. Leppanen

(Division Sign-Off) Division of Reproductive, A and Radiological Devices 510(k) Number

Over-the-Counter Use.

. (Optional Format 3-10-98)

Regulation Number and Section

§ 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.