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The ViraZyme® Culture Confirmation Screen for Influenza and Parainfluenza is intended for use as a screening test for respiratory viral cultures infected with influenza type A and B and parainfluenza types 1, 2, 3, and 4. This test will screen culture fluids for the presence of these viruses, but it is not indented for the definitive typing of these viruses.

Influenza and parainfluenza viruses posses surface glycoproteins with neuraminidase activity, that hydrolyze substrates which contain alphaketosidically linked N-acetylneuraminic acid (Neu5Ac). A modified Neu5Ac molecule has been synthesized and coupled to a chromogen to produce the neuraminidase substrate. In the presence of influenza and parainfluenza the chromogenic substrate is then cleaved by the action of viral neuraminidase, releasing a free chromogen. This free chromogen is then precipitated by combining with a diazonium salt to produce a red color. The red precipitate is then concentrated and collected from the solution onto a filter device.

Here's the analysis of the provided text regarding the acceptance criteria and study for the ViraZyme® Culture Confirmation Screen:

Note: The provided document is a 510(k) summary for a diagnostic test, not an AI/ML device. Therefore, several sections of your request (e.g., MRMC studies, AI improvement, training set details) are not applicable and will be marked as such.

1. Table of Acceptance Criteria and Reported Device Performance

The document does not explicitly state pre-defined acceptance criteria in terms of a specific sensitivity or specificity threshold. Instead, it presents the "Performance Characteristics" from several studies as the evidence of effectiveness. The general acceptance criterion implied is that the device demonstrates a high degree of agreement with standard culture confirmation methods using monoclonal antibodies (IFA).

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

The studies involved a total of 800 specimens across four locations.

• Southern medical center: 177 previously identified patient specimens (retrospective, from freeze). Data from the United States.
• Southwestern medical center: 97 previously identified patient specimens (retrospective, from freeze). Data from the United States.
• Midwestern medical center: 123 previously identified patient specimens (retrospective, from freeze). Data from the United States.
• In-house evaluation (Southwest): 403 previously identified frozen and fresh patient specimens (mix of retrospective and prospective). Data from the United States.

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

The ground truth was established by "standard culture confirmation with monoclonal antibodies (IFA)." This refers to laboratory testing, not human expert interpretation in the way one might consider a radiologist or pathologist. Therefore, the concept of "number of experts" or their specific qualifications for establishing ground truth as interpreted here (e.g., radiologist with X years of experience) is not applicable. The implicit "experts" are the trained medical technologists performing the standard IFA diagnostic tests.

4. Adjudication Method for the Test Set

Not applicable. The ground truth was established by a standard laboratory technique (IFA), not through a subjective interpretation that would require an adjudication method like 2+1 or 3+1.

5. 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

Not applicable. This is a diagnostic test kit, not an AI/ML device involving human readers or AI assistance.

6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) was done

This refers to the performance of the ViraZyme® assay itself (the "device") independently. The studies presented are standalone performance evaluations of the ViraZyme® assay compared to the IFA (Immunofluorescence Assay) gold standard. The device operates automatically by detecting the enzymatic reaction; there is no human-in-the-loop performance component beyond sample preparation and reading the color change.

7. The Type of Ground Truth Used

The ground truth used was "standard culture confirmation with monoclonal antibodies (IFA)". This is a well-established laboratory diagnostic method for viral identification and is considered the reference standard in this context.

8. The Sample Size for the Training Set

Not applicable. This is a chemical/enzymatic diagnostic assay, not an AI/ML algorithm that requires a "training set."

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

Not applicable, as there is no training set for this type of device.

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