The Dimension Vista™ Free Thyroxine Flex® reagent cartridge (FT4) is an in-vitro diagnostic test for the quantitative measurement of Free thyroxine in human serum and plasma.

The Dimension Vista™ LOCI I Calibrator is an in-vitro diagnostic product intended for the calibration of Thyroid Stimulating Hormone (TSH), Free Triodothyronine (FT3), and Free Thyroxine (FT4).

The Dimension Vista™ Free Thyroxine Flex® reagent cartridge (FT4) is a device intended to measure Free (not protein bound) thyroxine (thyroid hormone) in serum and plasma. Levels of free thyroxine in plasma are thought to reflect the amount of thyroxine hormone available to the cells and may therefore determine the clinical metabolic status of thyroxine. Measurements obtained by this device are used in the diagnosis and treatment of thyroid disease.

The Dimension Vista™ LOCI I Calibrator is a device intended for medical purposes for use in a the Dithenston + Iba - Dints of reference that are used in the determination of values in the test are creating of Free Thyroxine (FT4), Free Triiodothyronine (FT3), and Thyroid Stimulating Hormone (TSH) in human specimens.

Device Description

The FT4 method is a homogenous, sequential, chemiluminescent immunoassay based on Luminescent Oxygen Channeling Immunoassay (LOCI™) technology. The LOCI™ reagents include two latex bead reagents and a biotinylated anti-T4 mouse monoclonal antibody. The first bead reagent (Chemibeads) is coated with triiodothyronine (T3), a naturally occurring, weaker binding analog of T4. and contains chemiluminescent dye. The second bead reagent (Sensibeads) is coated with streptavidin and contains a photosensitizer dye. In a first step, sample is incubated with biotinylated antibody which allows T4 from the sample to saturate a fraction of the biotinylated antibody that is directly related to the free T4 concentration. In a second step, T3 chemibeads are added and form bead/ biotinylated antibody immunocomplexes with the non-saturated fraction of the biotinylated antibody. Sensibeads are then added and bind to the biotin to form bead pair immunocomplexes. When illuminated by light at 680 nm, sensibeads convert dissolved oxygen in the reaction solution into the singlet oxygen form ('O2). In the bead pairs, the singlet oxygen diffuses ("channels") into chemibeads, triggering a chemiluminescent reaction. The resulting chemiluminescent signal is measured at 612 nm and is an inverse function of the concentration of free T4 in the sample.

The Dimension Vista™ LOCI I Calibrator is a three level, liguid, multi-analyte product. This product's matrix is bovine serum albumin and it contains buffer, stabilizer and preservatives. Level A is a zero level, while levels B and C contain human thyroxine, triodothyronine and thyroid stimulating hormone. Values are assigned to the calibrator from a masterpool that is traceable through a patient correlation study to an existing comparative method for FT3 and FT4. The TSH value is referenced to the WHO standard, 2nd IRP 80/588, and confirmed with the 3rd IS 81/565.

AI/ML Overview

Here's an analysis of the provided text to extract the requested information about the acceptance criteria and the supporting study for the Dimension Vista™ Free Thyroxine Flex® reagent cartridge (FT4) and Dimension Vista™ LOCI 1 Calibrator:

1. Table of Acceptance Criteria and Reported Device Performance

Acceptance Criteria (Implicit)	Reported Device Performance (Dimension Vista™ FT4 vs. ADVIA Centaur FrT4)
Strong linear correlation	Correlation Coefficient (r) = 0.983
Slope close to 1	Slope = 1.03
Intercept close to 0	Intercept = 0.02

Note on Acceptance Criteria: The document does not explicitly state quantitative acceptance criteria (e.g., "r must be > X", "slope must be within Y", etc.). The acceptance is implicitly based on achieving "substantial equivalence" through method comparison that demonstrates a strong clinical correlation to the predicate device. The presented correlation statistics (slope, intercept, correlation coefficient) are the reported performance that met this implicit acceptance of substantial equivalence.

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

Sample Size: 108 clinical patient samples.
Data Provenance: The data refers to "clinical patient samples," implying human samples. The country of origin is not specified but is almost certainly the USA, given that the submission is to the FDA from a US-based company (Dade Behring Inc., Newark, DE). The study is retrospective in the sense that the samples were already collected and then analyzed by both methods.

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

This information is not provided in the document. For in-vitro diagnostic (IVD) devices like this, the "ground truth" for method comparison is typically the measurement obtained by the predicate device (ADVIA Centaur FrT4 assay), which is itself a legally marketed and presumably validated device. Therefore, expert consensus on individual patient results isn't typically established in the same way as for, say, an imaging AI product diagnosing disease. The predicate device's measurement serves as the standard.

4. Adjudication Method for the Test Set

This information is not applicable/provided for this type of IVD method comparison study. Adjudication methods (like 2+1, 3+1) are typically used in studies where human experts are making subjective assessments that need to be reconciled to establish a consensus ground truth, such as in imaging studies. For a quantitative measurement comparison between two devices, the "ground truth" is typically the measurement from the established predicate method, and no human adjudication of individual results against a "true" disease state is described.

5. If a Multi Reader Multi Case (MRMC) Comparative Effectiveness Study Was Done, and the Effect Size

No, a Multi Reader Multi Case (MRMC) comparative effectiveness study was not done. This type of study assesses how AI assistance impacts human reader performance (e.g., radiologists interpreting images). The study described here is a direct comparison of the new device's quantitative output (Free Thyroxine levels) against a predicate device's quantitative output, not an assessment of human interpretation with or without AI.

6. If a Standalone (Algorithm Only Without Human-in-the-Loop Performance) Was Done

Yes, a standalone performance evaluation was done. The study directly compares the performance of the Dimension Vista™ Free Thyroxine Flex® reagent cartridge (the "algorithm/device only") to the predicate device (ADVIA Centaur FrT4 assay). This is a direct measurement of the device's output, without human intervention in the result generation or interpretation that would typically define "human-in-the-loop" for device performance. The device produces a quantitative measurement, and its accuracy is assessed against the predicate's measurement.

7. The Type of Ground Truth Used

The ground truth used for the comparison study was the measurements obtained from the predicate device (ADVIA Centaur FrT4 assay). The study aimed to show "substantial equivalence" of the new device's measurements to those of an already legally marketed, established method.

8. The Sample Size for the Training Set

The document does not provide information on the sample size used for the training set. This is a 510(k) submission focused on the analytical performance for equivalence, not a detailed description of the device's internal development and training (if any 'machine learning' type training were involved, which is unlikely for this type of traditional immunoassay).

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

The document does not provide information on how the ground truth for a training set was established, as details about a training set are not mentioned. For the calibrator, the document states: "Values are assigned to the calibrator from a masterpool that is traceable through a patient correlation study to an existing comparative method for FT3 and FT4." This describes the calibration process, which uses reference materials traceable to comparative methods, rather than a "training set" for an AI algorithm.

Summary

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2006 MAR 3

K 05353/

Summary of Safety and Effectiveness Information

This summary of 510(k) safety and effectiveness information is being submitted in accordance with the requirements of SMDA 1990 and 21 CFR 807.92.

Submitter's Name:	Lorraine H Piestrak
	Dade Behring Inc.
	P.O. Box 6101
	Newark, DE 19714-6101

Date of Preparation: December 16, 2005

Name of Product:

Dimension Vista™ Free Thyroxine Flex® reagent cartridge (FT4) Dimension Vista™ LOCI 1 Calibrator

FDA Classification Name:

Free Thyroxine test system	(Class II)
Calibrator, Secondary	(Class II)

Predicate Device:

The following table describes the predicate devices, device classification, regulation and product code associated with this pre-market notification:

NewProduct	PredicateDevice	510(k)number	DeviceClass	Regulation	ProductCode
Dimension Vista™ FreeThyroxine (FT4) Flex® reagentcartridge	ADVIA Centaur FrT4 assay	unknown	II	862.1695	CEC
Dimension Vista™LOCI 1 Calibrator	Thyroid Calibrator	K970389	II	862.1150	JIT

Device Description:

The FT4 method is a homogenous, sequential, chemiluminescent immunoassay based on Luminescent Oxygen Channeling Immunoassay (LOCI™) technology. The LOCI™

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reagents include two latex bead reagents and a biotinylated anti-T4 mouse monoclonal antibody. The first bead reagent (Chemibeads) is coated with triiodothyronine (T3), a naturally occurring, weaker binding analog of T4. and contains chemiluminescent dye. The second bead reagent (Sensibeads) is coated with streptavidin and contains a photosensitizer dye. In a first step, sample is incubated with biotinylated antibody which allows T4 from the sample to saturate a fraction of the biotinylated antibody that is directly related to the free T4 concentration. In a second step, T3 chemibeads are added and form bead/ biotinylated antibody immunocomplexes with the non-saturated fraction of the biotinylated antibody. Sensibeads are then added and bind to the biotin to form bead pair immunocomplexes. When illuminated by light at 680 nm, sensibeads convert dissolved oxygen in the reaction solution into the singlet oxygen form ('O2). In the bead pairs, the singlet oxygen diffuses ("channels") into chemibeads, triggering a chemiluminescent reaction. The resulting chemiluminescent signal is measured at 612 nm and is an inverse function of the concentration of free T4 in the sample.

Intended Use:

The Dimension Vista™ Free Thyroxine Flex® reagent cartridge (FT4) is an in-vitro diagnostic test for the quantitative measurement of Free thyroxine in human serum and plasma.

The Dimension Vista™ LOCI I Calibrator is an in-vitro diagnostic product intended for the calibration of Thyroid Stimulating Hormone (TSH), Free Triodothyronine (FT3), and Free Thyroxine (FT4).

Comparison to Predicate Device:

Both the Dimension Vista™ Free Thyroxine Flex® reagent cartridge and the predicate Advia Centaur FrT4 assay employ prepackaged reagents for use on automated clinical chemistry test systems. A comparison of the important similarities and differences of these methods is provided in the following table:

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Feature	Dimension Vista™ FreeThyroxine (FT4) Flex® reagentcartridge	ADVIA Centaur FrT4 assay
Intended Use	in vitro diagnostic use	in vitro diagnostic use
Sample Type	Serum and Plasma	serum
Assay Range	0.1 - 8.0 ng/dL	0.1 - 12.0 ng/dL
Technology	chemiluminescent	chemiluminescent
Sample Size	10 µL	25 µL
Antibody	Anti - T4 mouse monoclonal	Anti -T4 rabbit polyclonal

Feature	Dimension Vista™ LOCI I Calibrator	Dimension® Thyroid Calibrator
Intended Use	in vitro diagnostic use	in vitro diagnostic use
Analytes	FT4, TSH, FT3	FT4, TSH
Matrix	Bovine Serum Albumin	Bovine Serum Albumin
Form	liquid	liquid
Volume	A 2.5 mL per vialB 1.5 mL per vialC 2.0 mL per vial	2 mL per vial
Levels	3 levels	5 levels

Comments on Substantial Equivalence:

Split sample comparison between the Dimension Vista™ FT4 Flex™® reagent cartridge and ADVIA Centaur FrT4 assay gave the following correlation statistics, when tested with clinical patient samples:

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DimensionVista™	Predicate	SampleType	Slope	Intercept	CorrelationCoefficient (r)	n
FT4	ADVIA CentaurFrT4	Serum	1.03	0.02	0.983	108

Method Comparison Data sion VistaTM FT4 vs Predicate Method

Conclusion:

The Dimension Vista™ FT4 Flex® reagent cartridge with the associated LOCI I calibrator is substantially equivalent in principle and performance to the ADVIA Centaur FrT4 assay based on the split sample comparison discussed above.

Louanie H Restrole

Lorraine H Piestrak Regulatory Affairs & Compliance Manager December 16, 2005

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DEPARTMENT OF HEALTH & HUMAN SERVICES

Image /page/4/Picture/1 description: The image contains the text "Public Health Service". The text is arranged on a single line. The font is simple and easy to read. The text is likely part of a document or sign.

Image /page/4/Picture/2 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" arranged around the perimeter. Inside the circle is an abstract symbol resembling an eagle or bird in flight, composed of three curved lines.

2006 MAR 3

Food and Drug Administration 2098 Gaither Road Rockville MD 20850

Ms. Lorraine H. Piestrak Regulatory Affairs & Compliance Manager Dade Behring Inc. PO Box 6101, M/S 514 Newark DE 19714- 6101

Re: K053531

Trade/Device Name: Dimension Vista™ Free Thyroxine Flex® reagent cartridge (FT4) Dimension Vista™ LOCI 1 Calibrator Regulation Number: 21 CFR$862.1695 Regulation Name: Free thyroxine test system Regulatory Class: Class II Product Code: CEC, JIT Dated: December 16, 2005 Received: December 19, 2005

Dear Ms. Piestrak:

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 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 requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820).

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Page 2 --

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 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 vours,

Alberto Gutz

Alberto Gutierrez, Ph.D. Director Division of Chemistry and Toxicology 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): K053531

Dimension Vista™ Free Thyroxine Flex® reagent cartridge (FT4) Device Name:

Indications For Use:

Prescription Use X (Part 21 CFR 801 Subpart D) AND/OR

Over-The-Counter Use --------(21 CFR 801)

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

Concurrence of CDRH, Office of In Vitro Diagnostic Devices (OIVD)

ivision Sign-Off

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Office of In Vitro Diagnostic Device Evaluation and Safety

510(k) K053531

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Indications for Use

510(k) Number (if known): K053553

Device Name:

Dimension Vista™ LOCI 1 Calibrator

Indications For Use:

Prescription Use X (Part 21 CFR 801 Subpart D) AND/OR

Over-The-Counter Use --------(21 CFR 801)

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

Concurrence of CDRH, Office of In Vitro Diagnostic Devices (OIVD)

g Page 1 of

C.H

Division Sign-Off

Office of In Vitro Diagnostic Device Evaluation and Safety

510(k) K053531

Regulation Number and Section

§ 862.1695 Free thyroxine test system.

(a)
Identification. A free thyroxine test system is a device intended to measure free (not protein bound) thyroxine (thyroid hormone) in serum or plasma. Levels of free thyroxine in plasma are thought to reflect the amount of thyroxine hormone available to the cells and may therefore determine the clinical metabolic status of thyroxine. Measurements obtained by this device are used in the diagnosis and treatment of thyroid diseases.(b)
Classification. Class II.