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The S TEST Reagent Cartridge Lactate Dehydrogenase (LD) is intended for the quantitative determination of LD in serum and plasma using the HITACHI Clinical Analyzer E40. The S TEST Reagent Cartridge Lactate Dehydrogenase (LD) is intended for use in clinical laboratories or physician office laboratories. For in vitro diagnostic use only. Measurements of LD are used in the diagnosis and treatment of liver and cardiac diseases.

The S TEST Reagent Cartridge Amylase (AMY) is intended for the quantitative determination of AMY in serum and plasma using the HITACHI Clinical Analyzer E40. The S TEST Reagent Cartridge Amylase (AMY) is intended for use in clinical laboratories or physician office laboratories. For in vitro diagnostic use only. Measurements of AMY are mainly used in the diagnosis and treatment of pancreatic diseases.

The Hitachi Clinical Analyzer is an automatic, bench-top, wet chemistry system intended for use in clinical laboratories or physician office laboratories. The instrument consists of a desktop analyzer unit, an operations screen that prompts the user for operation input and displays data, a printer, and a unit cover. The analyzer unit includes a single probe, an incubation rotor, carousels for sample cups and reagent cartridges, and a multi-wavelength photometer. The single-use reagent cartridges may be placed in any configuration on the carousel, allowing the user to develop any test panel where the reagent cartridges are available.

The S TEST reagent cartridges are made of plastic and include two small reservoirs capable of holding two separate reagents (R1 and R2), separated by a reaction cell/photometric cuvette. The cartridges also include a dot code label that contains all chemistry parameters, calibration factors, and other production-related information, e.g., expiration dating. The dimensions of the reagent cartridges are: 13.5 mm (W) × 28 mm (D) × 20.2 mm (H).

System operation: After the sample cup is placed into the carousel, the analyzer pipettes the sample, pipettes the reagent, and mixes (stirs) the sample and reagent together. After the sample and reagent react in the incubator bath, the analyzer measures the absorbance of the sample, and based on the absorbance of the reactions, it calculates the concentration of analyte in the sample. The test system can measure analytes in serum or plasma and results are available in approximately 15 minutes per test. This submission is for Reagent Cartridge ALP.

Chemistry reactions: (LD) Lactate dehydrogenase in samples catalyzes the reaction of converting lactic acid to pyruvic acid. During this reaction, NAD is converted into NADH with an increase in absorbance at 340 nm. The LD activity can be determined by measuring the production rate of the resulting NADH.

(AMY) Amylase in blood samples reacts with the substrate alfa-2-chloro-4-nitropheny]galactopyranosylmaltoside (Gal-G2-CNP), and the substrate is cleaved into 4galactopyranosylmaltose (Gal-G2) and 2-chloro-4-nitrophenol (CNP). Amylase activity is determined by measuring the production rate of CNP (yellow).

Here's a breakdown of the acceptance criteria and the study details for the Hitachi Chemical Diagnostics S TEST Reagent Cartridges for Lactate Dehydrogenase (LD) and Amylase (AMY):

1. Table of Acceptance Criteria and Reported Device Performance

The acceptance criteria for this device are implied by the reported performance and comparison to predicate devices, rather than explicitly stated as discrete pass/fail thresholds in a formal table from the provided text. However, we can infer the expected performance based on the studies conducted.

S TEST Reagent Cartridge Lactate Dehydrogenase (LD)

S TEST Reagent Cartridge Amylase (AMY)

2. Sample Size and Data Provenance for the Test Set

• 10-day In-house Precision (LD, AMY):
  • Sample Size: Three levels of samples were tested. Each level was tested in two runs, twice a day, for 20 days. This implies a significant number of replicates (e.g., 3 levels * 2 runs/day * 2 times/day * 20 days = 240 measurements per analyte, though typically results are grouped for analysis). The text explicitly states 30 replicates per sample per site for the external precision studies.
  • Data Provenance: Not explicitly stated, but "in-house" implies from the manufacturer's laboratory. "Clinical specimens" for method comparison suggest human samples.
• Method Comparison (LD):
  • Sample Size (Test Set): 106 clinical specimens.
  • Data Provenance: Not explicitly stated, but "clinical specimens" implies human samples, presumably retrospective or prospectively collected for the study. No country of origin is mentioned.
• Method Comparison (AMY):
  • Sample Size (Test Set): 105 clinical specimens.
  • Data Provenance: Not explicitly stated, but "clinical specimens" implies human samples, presumably retrospective or prospectively collected for the study. No country of origin is mentioned.
• Matrices Comparisons (LD):
  • Sample Size (Test Set): 39 matched serum/plasma samples.
  • Data Provenance: Not explicitly stated; "clinical samples" implies human.
• Matrices Comparisons (AMY):
  • Sample Size (Test Set): Approximately 43 matched serum/plasma samples.
  • Data Provenance: Not explicitly stated; "clinical samples" implies human.
• External Site Precision (LD, AMY):
  • Sample Size (Test Set): Three blinded serum samples (low, middle, high concentrations for each analyte). Each sample was assayed six times per day for five days, yielding 30 replicates per sample per site. This was done at three external sites.
  • Data Provenance: "three external POL-type sites" (Physician Office Laboratory-type sites). Implies human serum samples.
• External Site Method Comparison (LD):
  • Sample Size (Test Set): Approximately 70-80 serum specimens (specifically, 87 for Site 1, 78 for Site 2, 86 for Site 3).
  • Data Provenance: "three external POL-type sites" using "serum specimens with LD values". Implies human serum samples.
• External Site Method Comparison (AMY):
  • Sample Size (Test Set): Approximately 70-80 serum specimens (specifically, 76 for Site 1, 69 for Site 2, 71 for Site 3).
  • Data Provenance: "three external POL-type sites" using "serum specimens with AMY values". Implies human serum samples.

3. Number of Experts and Qualifications for Ground Truth

This device is a quantitative diagnostic test for measuring enzyme levels (LD and AMY) in blood samples, typically analyzed by laboratory equipment. The "ground truth" for such devices is established by validated reference methods or predicate devices, not typically by expert review of images or clinical assessments in the same way an AI diagnostic imaging device would use radiologists.

• For Method Comparison studies, the "ground truth" or reference method was "a standard laboratory system" (in-house studies) or "a comparative method as the reference method" (external POL studies). These are assumed to be legally marketed and validated laboratory instruments. No human experts are described as establishing "ground truth" in this context.

4. Adjudication Method for the Test Set

Not applicable for this type of quantitative diagnostic device. Adjudication methods like 2+1 or 3+1 are used in interpretation tasks (e.g., radiology for AI devices) where human judgment is pooled to establish a consensus ground truth. Here, the "ground truth" is determined by the output of a reference laboratory instrument or method.

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

No. An MRMC study is not relevant for this type of device, which is an automated quantitative assay. This device does not involve human readers interpreting images or clinical data with or without AI assistance. The studies performed compare the device's quantitative output to established reference methods or predicate devices.

6. Standalone (Algorithm Only Without Human-in-the-Loop Performance) Study

Yes, the studies described are standalone performance assessments of the device (Hitachi E40 Clinical Analyzer with S TEST Reagent Cartridges). The performance characteristics (analytical sensitivity, linearity, precision, interference, method comparison, matrices comparison) evaluate the instrument and reagent system's ability to accurately and precisely measure the target analytes entirely autonomously. There is no human interaction in producing the raw quantitative result from the device.

7. Type of Ground Truth Used

The ground truth used for performance evaluation was:

• Validated Reference Methods / Predicate Devices: For linearity, analytical sensitivity, and method comparison studies, the Hitachi E40 system results were compared against established reference methods or legally marketed predicate devices (Roche cobas c systems LDHI2 and AMYL2). The specific details of these reference methods are not provided but are generally understood to be highly accurate and precise laboratory assays.
• Known Concentrations: For precision studies, samples with "low, middle, and high concentrations" were used, implying that the approximate target concentrations were known or characterized.
• Spiked Samples: For interference studies, substances were added to samples at known concentrations to assess their impact on the assay (e.g., "50 mg/dL bilirubin").

8. Sample Size for the Training Set

This information is not provided in the summary. For a medical device like this (a reagent cartridge and analyzer), there isn't typically a "training set" in the sense of machine learning. The device's operational parameters, algorithms (for calculation), and calibration are established during its design and development, likely using extensive internal testing and optimization. Manufacturers establish operating procedures and calibration protocols based on R&D, not a discrete "training set" in the AI sense.

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

Given that this is a traditional in-vitro diagnostic device and not a machine learning algorithm, the concept of a "training set" and establishing "ground truth" for it, as typically understood in AI/ML, does not directly apply. The "ground truth" for developing the device itself would stem from fundamental principles of analytical chemistry, enzyme kinetics, and rigorous laboratory validation processes using primary calibrators and reference materials. The device's calibration curves and internal calculations are based on well-established scientific principles and extensive validation during its development phase.

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