The Chrono-log Model 700 Aggregometer measures platelet function on patient samples using electrical impedance in whole blood or optical density in plasma. The Model 700 Aggregometer has the capability to simultaneously measure ATP release with either method using luminescence. The Model 700 Aggregometer is also used to run the Ristocetin Cofactor Assay which is used to diagnose patients with von Willebrands disease. The instrument comes with a starter kit consisting of the following Chrono-log reagents and supplies: ADP, Arachondic Acid, Collagen, Epinephrine, Ristocetin, Thrombin, a CHRONO-LUME® Kit, a Ristocetin Cofactor Kit, cuvettes, stir bars and pipettes. The output of the Model 700 can be connected to either a strip chart recorder or to a Computer. Software is provided the computer interface option. The computer interface option is used to collect data only. The computer is not used for diagnosis or treatment and does not have any control over or input into the Model 700 Aggregometer.

AI/ML Overview

Here's an analysis of the provided text, focusing on the acceptance criteria and study details for the Chrono-log Model 700 Whole Blood Lumi-Aggregometer:

Acceptance Criteria and Device Performance

The provided document describes a 510(k) submission, which aims to demonstrate "substantial equivalence" to a legally marketed predicate device, rather than establishing explicit acceptance criteria with pre-defined thresholds for performance. The "acceptance criteria" here are implicitly linked to achieving a high correlation with the predicate devices, indicating comparable performance.

Here's a table summarizing the reported device performance, with the understanding that the "acceptance criteria" were met by demonstrating strong correlation:

Performance Metric	Acceptance Criteria (Implicit)	Reported Device Performance (Pearson Correlation Coefficient)	P-value
Optical Aggregation in PRP	Strong correlation with predicate Model 560	0.8204	< 0.0001
ATP Release by Luminescence in PRP	Strong correlation with predicate Model 560	0.6526	< 0.0001
Impedance Aggregation in Whole Blood	Strong correlation with predicate Model 560	0.7798	< 0.0001
ATP Release by Luminescence in Whole Blood	Strong correlation with predicate Model 560	0.7244	< 0.0001
Disposable Electrode Performance	Results within the normal range of predicate Model 591A/592A	Qualitative comparison of absolute values shown to be within range.	N/A

Study Details

Here's the breakdown of the study information based on your requested categories:

Sample size used for the test set and the data provenance:
- Optical Aggregation in PRP: 149 comparison tests
- ATP Release by Luminescence in PRP: 167 luminescence tests
- Impedance Aggregation in Whole Blood: 267 comparison tests
- ATP Release by Luminescence in Whole Blood: 300 luminescence tests
- Disposable Electrode Comparison: The table lists individual reagent tests (e.g., ADP 5, Collagen 2), but a total sample size for this specific comparison isn't explicitly stated beyond the reagent-specific values.
- Data Provenance: "Whole blood and Platelet Rich Plasma samples from normal, healthy, drug free subjects" were used. The country of origin is not specified, but given the submission is to the FDA, it is likely the US. The study appears to be prospective as comparison studies were "run" to compare the new device to existing ones.
Number of experts used to establish the ground truth for the test set and the qualifications of those experts (e.g., radiologist with 10 years of experience):
- The document does not mention the use of experts to establish ground truth in the context of these comparison studies. The ground truth in this type of submission is typically derived from the performance of the legally marketed predicate device itself.
Adjudication method (e.g. 2+1, 3+1, none) for the test set:
- "None" explicitly stated. The comparison is directly between the new device and the predicate device's measurements. There is no mention of independent adjudication of results.
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:
- No, a multi-reader, multi-case comparative effectiveness study was not performed. This device is a quantitative laboratory instrument, not an AI-assisted diagnostic imaging tool that would involve human readers.
If a standalone (i.e. algorithm only without human-in-the-loop performance) was done:
- Yes, this study represents a standalone performance evaluation of the Model 700 device itself, comparing its measurements to those of the predicate devices. There is no human-in-the-loop component in the measurement process. The device's output can be connected to a computer for data collection, but the computer is explicitly stated as "not used for diagnosis or treatment and does not have any control over or input into the Model 700 Aggregometer."
The type of ground truth used (expert consensus, pathology, outcomes data, etc.):
- The ground truth is established by the measurements obtained from the legally marketed predicate devices (Chrono-log Model 560 and Model 591A/592A). The concept of "ground truth" here is the established, accepted performance of the existing, equivalent devices. For the disposable electrodes, the ground truth is that the results should be "within the normal range as shown in the model 591A/592A Instruction Manual."
The sample size for the training set:
- The document does not specify a training set. This is a comparison study for a new iteration of an existing mechanical/electronic instrument, not a machine learning or AI algorithm that typically requires a separate training set.
How the ground truth for the training set was established:
- Not applicable, as no training set is mentioned or implied for this type of device comparison study.

Summary

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OCT 1 4 2005

K050265

11. 510(k) Summary

Device: Model 700 - Chrono-log Whole Blood Lumi-Aggregometer

Date: February 3, 2005

Submitted by: Chrono-log Corp., 2 West Park Rd., Havertown, PA 19083

Contact: Nicholas J. Veriabo (610) 853-1130

Name of Device:

Trade/Proprietary Name - Model 700 Chrono-log Whole Blood Lumi-Aggregometer

Common/Usual Name - Chrono-log Whole Blood Lumi-Aggregometer

Classification Name - System, Automatic Platelet Aggregation

After examining the test data included in this application, we have found the Chrono-log Model 700 Whole Blood Lumi-Aggregometer to be substantially equivalent to Chrono-log Model 560 Whole Blood Lumi-Aggregometer (K830749) with AGGRO/LINK Interface (K851025).

11.1 Device Description:

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11.2 Intended Use:

For in-vitro diagnostic use for measuring platelet aggregation and ATP secretion in whole blood or platelet rich plasma.

11.3 Technical Description:

The Chrono-log Model 700 Aggregometer is an Instrument used in the Laboratory for the determination of Platelet Aggregation in samples of either PRP or whole blood specimens with simultaneous measurement of ATP release. For this application, the Model 700 is claiming substantial equivalency to the Chrono-log Corporation's Model 560 Aggregometer (K830749) with the Model 810 AGGRO/LINK (K851025) computer interface option currently in commercial distribution by Chrono-log Corp. The Model 700 has the ability to use the Chrono-log Disposable electrodes for which we demonstrate substantial equivalency to the Chrono-log Model 591A/592A (K032951) also currently in commercial distribution by Chrono-log Corporation.

The Model 700 Aggregometer uses many of the same parts as the Model 560 such as: Heater Blocks that hold the samples, LED and Photodiode circuit boards that measure changes in optical density for turbidometric aggregation, Impedance Electrodes used for impedance measurements in whole blood. Photomultiplier Tubes for measuring ATP release and stirring motors for sample stirring. The circuitry that connects to the measuring devices has been changed to more modern circuits. Provisions have been made so that the printed circuit boards for computer interface option can be placed inside the Aggregometer rather than be housed in a stand alone unit.

The chassis has also been redesigned and the front panel is improved with a Liquid Crystal Display (LCD) for displaying Temperature, Stirring Speed and Gain. The new front panel controls are tactile membrane switches. The chassis itself is shaped differently and has the ability for two units to interface together into a four channel configuration.

The output of the Model 700 series can be connected to either a strip chart recorder or to a Computer. Chrono-log provides software for the computer interface option as an accessory. The computer interface option is used to collect data and is not used for diagnosis or treatment and does not have any control over or input into the Model 700 Aggregometer.

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11.4 Performance:

Comparison studies were run to compare the performance of the Model 700 to the Model 560 and the Model 591A for the disposable electrodes. Whole blood and Platelet Rich Plasma samples from normal, healthy, drug free subjects were tested with both instruments. The samples were tested using Chrono-log Collagen, ADP, Ristocetin, Epinephrine, Arachidonic Acid and Thrombin Reagents. The simultaneous measurement of ATP release was also measured using the luminescence technique. For ATP measurement CHRONO-LUME® was added to the sample.

The following concentrations of reagents were run: Collagen 2ug/mL and Spg/mL, ADP 5uM and 10uM, Arachidonic Acid 0.5 mM, Epinephrine SuM in PRP aggregation only, Ristocetin 1.0mg/mL for Whole Blood Aggregation and 1.25 mg/mL for PRP Aggregation and Thrombin for Luminescence measurement.

In Platelet Rich Plasma there were 149 comparison tests using optical aggregation with 167 Luminescence tests. In Whole Blood there were 267 comparison tests with Impedance Aggregation with 300 Luminescence tests. Although Aggregation and Luminescence are run simultaneously, there are always more Luminescence tests, because Aggregation is not measured with the thrombin reagent. At the recommended concentration, thrombin causes the platelets to clump in a single mass, which does not provide useful aggregation information. Thrombin at 1 unit concentration is used to measure the total amount of ATP in the platelets by Luminescence.

The Tables below show the correlation between the Model 700 and the Model 560

TABLE 9-1 Optical Aggregation in PRP

No. of Samples	Pearson correlation coefficient	P-value
149	0.8204	< 0.0001

TABLE 9-2 ATP Release by Luminescence in PRP

No. of Samples	Pearson correlation coefficient	P-value
167	0.6526	< 0.0001

TABLE 9-3 Impedance Aggregation in Whole Blood

No. of Samples	Pearson correlation coefficient	P-value
267	0.7798	< 0.0001

TABLE 9-4 ATP Release by Luminescence in Whole Blood

No. of Samples	Pearson correlation coefficient	P-value
300	0.7244	< 0.0001

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Also, we conducted a comparison of the Model 700 to the to the Model 591A/592A using disposable electrodes. Below is a table comparing the results.

DISPOSABLE ELECTRODE COMPARISON
REAGENT	700	592A
ADP 5	14	9
ADP 10	10	13
Collagen 2	18	14
Collagen 5	15	17
Risto .4	14	8
Risto .4	26	27
Risto .15	4	6
Risto .15	1	2

The results of both instruments are within the normal range as shown in the model 591 A/592A Instruction Manual.

The results of our validation study, demonstrates that the Model 700 and the Model 560 are substantially equivalent devices. We further demonstrate that when disposable Electrodes are used in the Model 700, the results are substantially equivalent to the results of the Model 591A/592A ..

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Image /page/4/Picture/1 description: The image shows the logo for the U.S. Department of Health & Human Services. The logo consists of a circular seal with the text "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" around the perimeter. Inside the circle is a stylized image of an eagle with its wings spread.

OCT 1 4 2005

Food and Drug Administration 2098 Gaither Road Rockville MD 20850

Mr. Nicholas J. Veriabo Executive Director Chrono-Log Corportation 2 West Park Road Havertown, Pennsylvania 19083-4691

K050265 Re: Trade/Device Name: Chrono-Log Model 700 Whole Blood Lumi-Aggregometer Regulation Number: 21 CFR § 864.5700 Regulation Name: Automated platelet aggregation system Regulatory Class: II Product Code: JOZ Dated: September 2, 2005 Received: September 7, 2005

Dear Mr. Veriabo:

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 101 ass balled in the May 28, 1976, the enactment date of the Medical Device Amendments, or to econmerces 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 such additional controls. Existing major regulations affecting your device can be found in Title 21, Code of Federal Regulations (CFR), Parts 800 to 895. 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 Parts 801 and 809); and good manufacturing practice SI requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820). 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.

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Page 2 -

If you desire specific information about the application of labeling requirements to your device, or questions on the promotion and advertising of your device, please contact the Office of In Vitro Diagnostic Device Evaluation and Safety at (240) 276-0484. 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 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/industry/support/index.html

Sincerely yours,

Robert Beckerh

Robert L. Becker, Jr., MD, Pa Director Division of Immunology and Hematology Office of In Vitro Diagnostic Device Evaluation and Safety Center for Devices and Radiological Health

Enclosure

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Indications for Use

510(k) Number (if known):

#050264 K650264 S

Device Name:

Chrono-log Model 700 Whole Blood Lumi-Aggregometer

Indications For Use:

For in-vitro diagnostic use for measuring platelet aggregation and ATP secretion in whole blood or platelet rich plasma.

Prescription Use (Part 21 CFR 801 Subpart D)

AND/OR

Over-The-Counter Use (21 CFR 807 Subpart C)

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

Concurrence of CDRH, Office of Ja Vitro Djagnøstic Devices (OIVD)

Division Sign-Off

Office of In Vitro Diagnostic Device Evaluation and Safety

Page 1 of __

510(k) Kos0265

Regulation Number and Section

§ 864.5700 Automated platelet aggregation system.

(a)
Identification. An automated platelet aggregation system is a device used to determine changes in platelet shape and platelet aggregation following the addition of an aggregating reagent to a platelet-rich plasma.(b)
Classification. Class II (performance standards).