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The Alere™ i Influenza A & B assay performed on the Alere™ i Instrument is a rapid molecular in vitro diagnostic test utilizing an isothermal nucleic acid amplification technology for the qualitative detection and discrimination of influenza A and B viral RNA in nasal swabs from patients with signs and symptoms of respiratory infection. It is intended for use as an aid in the differential diagnosis of influenza A and B viral infections in humans in conjunction with clinical and epidemiological risk factors. The assay is not intended to detect the presence of influenza C virus.

Negative results do not preclude influenza virus infection and should not be used as the sole basis for diagnosis, treatment or other patient management decisions.

Performance characteristics for influenza A were established during the 2012-2013 influenza season when influenza A/H3 and A/H1N1 pandemic were the predominant influenza A viruses in circulation. When other influenza A viruses are emerging, performance characteristics may vary.

If infection with a novel influenza A virus is suspected based on current clinical and epidemiological screening criteria recommended by public health authorities, specimens should be collected with appropriate infection control precautions for novel virulent Influenza viruses and sent to state or local health department for testing. Viral culture should not be attempted in these cases unless a BSL 3+ facility is available to receive and culture specimens.

Alere™ i Influenza A & B is a rapid, instrument-based isothermal test for the qualitative detection and differentiation of influenza A and influenza B from nasal swab specimens collected from patients presenting with signs and symptoms of respiratory infection. The Alere™ i Influenza A & B System utilizes isothermal nucleic acid amplification technology and is comprised of:

• Sample Receiver single use, disposable containing the elution buffer .
• . Test Base - single use, disposable comprising two sealed reaction tubes, each containing a lyophilized pellet
• Transfer Cartridge single use, disposable for transfer of the eluted sample to the Test Base, and .
• Alere™ i Instrument repeat use reader .

The reaction tubes in the Test Base contain the reagents required for amplification of the target nucleic acid and an internal control. Alere™ i Influenza A & B utilizes a pair of templates (similar to primers) for the specific amplification of RNA from influenza A and B and a fluorescently labeled molecular beacon designed to specifically identify the amplified RNA targets. Alere™ i Influenza A & B is performed within the confinement of the Test Base, and no other part of the Alere™ i Instrument has contact with the sample during the amplification process. This minimizes the risk of instrument contamination and sample carryover between measurements.

To perform the assay, the Sample Receiver and Test Base are inserted into the Alere™ i Instrument and the elution buffer is automatically the instrument. The sample is added to the Sample Receiver and transferred via the Transfer Cartridge to the Test Base, resuspending the lyophilized pellet contained within the Test Base and initiating target amplification. Heating, mixing and detection by fluorescence is provided by the instrument, with results automatically reported.

Results are displayed by the Alere™ i Instrument separately for influenza A and influenza B. Results are also stored in an on-board archive and are assigned to a sample ID that has been entered into the Alere™ i Instrument by the operator, and the date/time the test was performed. Data can be retrieved and downloaded by the operator at any time after testing. An external Alere™ Universal Printer can be attached via USB to the Alere™ i Instrument to print test results.

Here's a breakdown of the acceptance criteria and the study that proves the device meets them, based on the provided text:

1. Table of Acceptance Criteria and the Reported Device Performance

The acceptance criteria are implied by the reported performance metrics, particularly sensitivity and specificity, as these are critical for diagnostic devices. While explicit numerical targets for "acceptance criteria" are not given in a dedicated section, regulatory submissions typically require performance within acceptable clinical ranges. For this summary, I'll extract the reported performance from the clinical study as the device's demonstrated capability.

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

• Sample Size: 585 evaluable direct nasal swab specimens.
  • Influenza A performance analysis: 571 specimens
  • Influenza B performance analysis: 569 specimens
• Data Provenance: Prospective study conducted in the U.S. during the 2012-2013 flu season. Specimens were collected from patients presenting with flu-like symptoms at eight investigational sites throughout the U.S.

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

The ground truth for the clinical study was established using viral culture performed according to standard virology culture procedures. The text does not specify the number of individual experts (e.g., virologists) or their specific qualifications (e.g., years of experience) involved in performing the viral cultures, beyond stating "standard virology culture procedures." It mentions that six of the eight sites shipped samples to a central testing laboratory for viral culture, and two sites performed culture on-site with a local laboratory.

4. Adjudication Method for the Test Set

Discrepant results between the Alere™ i Influenza A & B device and viral culture were investigated. The adjudication method involved:

• Testing the discrepant specimens using an FDA-cleared Influenza RT-PCR assay at a central testing laboratory. This RT-PCR assay served as a tie-breaker or confirmatory test to resolve inconsistencies.

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

This device, the Alere™ i Influenza A & B, is a fully automated in vitro diagnostic test for qualitative detection of viral RNA. It's not an AI-assisted diagnostic device that human readers interact with or interpret. Therefore, an MRMC comparative effectiveness study comparing human readers with and without AI assistance is not applicable and was not performed. The device provides an automated result.

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

Yes, a standalone performance study was done. The entire clinical study, as described, evaluates the performance of the Alere™ i Influenza A & B system as an automated algorithm providing qualitative results (positive/negative) for Influenza A and B. The results are "automatically reported" by the instrument and do not involve human interpretation of complex data output from the device to arrive at the final diagnostic decision.

7. The Type of Ground Truth Used (Expert Consensus, Pathology, Outcomes Data, etc.)

The primary ground truth used for the clinical study was viral culture. For discrepant results, an FDA-cleared Influenza RT-PCR assay was used as a confirmatory method.

8. The Sample Size for the Training Set

The provided text describes the clinical validation study (test set) for the device. It does not specify the sample size for a training set. This is common for diagnostic assays where the "training" (development and optimization) phase might use internally developed samples or smaller pilot studies, and the submission focuses on the independent clinical validation. Analytical studies (e.g., LoD, reactivity) used contrived specimens which are distinct from training clinical samples.

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

Since a dedicated training set sample size is not specified, the method for establishing its ground truth is also not detailed in this document. However, based on typical diagnostic assay development, ground truth for any internal development/training samples would likely also rely on well-characterized viral strains, viral culture, or highly sensitive and specific molecular methods to confirm presence/absence and concentration of the target analytes. For analytical studies mentioned, ground truth was established by known concentrations of verified virus strains (TCID50/mL, EID50/mL, Genome Equivalents/mL).

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The Alere™ Influenza A & B Test is an in vitro immunochromatographic assay for the qualitative detection of influenza A and B nucleoprotein antigens in nasal swab specimens collected from symptomatic patients. It is intended to aid in the rapid differential diagnosis of influenza A and B viral infections. Negative test results are presumptive and should be confirmed by cell culture or an FDA-cleared influenza A and B molecular assay. Negative test results do not preclude influenza viral infection and should not be used as the sole basis for treatment or other patient management decisions.

The Alere™ Influenza A & B Test is an immunochromatographic membrane assay that uses highly sensitive monoclonal antibodies to detect influenza type A and B nucleoprotein antigens in nasal swab specimens. These antibodies and a control protein are immobilized onto a membrane support as three distinct lines and are combined with other reagents/pads to construct a Test Strip.

Nasal swab samples are added to a Coated Reaction Tube to which an extraction reagent has been added. An Alere™ Influenza A & B Test Strip is then placed in the Coated Reaction Tube holding the extracted liquid sample. Test results are interpreted at 10 minutes based on the presence of pink-to-purple colored Sample Lines. The yellow Control Line turns blue in a valid test.

Here's an analysis of the provided text, outlining the acceptance criteria and study details for the Alere™ Influenza A & B Test:

The Alere™ Influenza A & B Test is an in vitro immunochromatographic assay for the qualitative detection of influenza A and B nucleoprotein antigens in nasal swab specimens. It's intended to aid in the rapid differential diagnosis of influenza A and B viral infections.

Acceptance Criteria and Device Performance

The provided document details the performance of the Alere™ Influenza A & B Test against viral culture as the ground truth. While explicit "acceptance criteria" are not stated as target thresholds in this document, the reported performance metrics are presented against the comparison method. We can infer the implied acceptance would be that the device demonstrates adequate diagnostic accuracy (sensitivity and specificity) to be useful for its intended purpose.

Here's the performance as reported in the clinical study:

Study Details

2. Sample Size and Data Provenance

• Test Set Sample Size: A total of 470 prospective nasal swab specimens were evaluated.
• Data Provenance:
  • Country of Origin: The study was conducted at seven U.S. trial sites.
  • Retrospective/Prospective: The study was a "multi-center, prospective, clinical study conducted at seven U.S. trial sites during the 2008-2009 respiratory season."

3. Number of Experts and Qualifications for Ground Truth

The document does not explicitly state the number or specific qualifications of experts used to establish the ground truth (viral culture). Viral culture itself is a laboratory gold standard, and its interpretation would typically be performed by trained laboratory personnel or microbiologists.

4. Adjudication Method for the Test Set

The document does not describe a formal adjudication method (e.g., 2+1, 3+1) for discordant results between the Alere™ Influenza A & B Test and viral culture for the primary clinical study. However, for the 19 samples where the Alere™ test was negative but culture was positive for influenza B, an investigational RT-PCR assay was used. "Ten (10) of these samples were negative for influenza B by PCR," suggesting a form of secondary confirmation for these specific discrepancies.

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

There is no indication that a multi-reader multi-case (MRMC) comparative effectiveness study was done to assess how much human readers improve with AI vs. without AI assistance. This device is a rapid diagnostic test (immunochromatographic assay), not an AI-assisted diagnostic tool for image interpretation or complex data analysis that would typically involve human readers interpreting results.

6. Standalone Performance

Yes, the clinical study directly assesses the standalone performance (algorithm only, without human-in-the-loop performance) of the Alere™ Influenza A & B Test. The reported sensitivity, specificity, and invalid rate are for the device itself against the viral culture.

7. Type of Ground Truth Used

The primary ground truth used for the clinical study was viral culture.
For discordant Influenza B results (Alere negative, culture positive), an investigational RT-PCR assay was used as a secondary confirmation method.

8. Sample Size for the Training Set

The document does not specify a separate "training set" sample size in the context of device development for this immunochromatographic assay. Such devices are typically developed through analytical studies and optimization of reagents, rather than machine learning models that require distinct training sets. The "Analytical Sensitivity" section involved testing various concentrations of influenza viruses, which could be considered part of the development and optimization process, but not a typical "training set" in the AI sense.

9. How Ground Truth for the Training Set Was Established

As there is no explicit "training set" in the context of a machine learning algorithm, the concept of establishing ground truth for a training set does not directly apply here. The analytical studies (Analytical Sensitivity, Analytical Reactivity, Analytical Specificity) used well-characterized viral strains and microorganisms, where their presence and concentration served as the known "ground truth" for evaluating the immunoassay's performance characteristics. This would involve laboratory-established concentrations and identification of these biological agents.

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The Alere BinaxNOW® Influenza A & B Card is an in vitro immunochromatographic assay for the qualitative detection of influenza A and B nucleoprotein antigens in nasopharyngeal (NP) swab, nasal swab, and nasal wash/aspirate specimens. It is intended to aid in the rapid differential diagnosis of influenza A and B viral infections. Negative test results are presumptive and should be confirmed by cell culture or an FDA-cleared influenza A and B molecular assay. Negative test results do not preclude influenza viral infection and should not be used as the sole basis for treatment or other patient management decisions.

Caution: Assay sensitivity for nasal wash/aspirate samples was determined primarily using archived specimens. Users may wish to establish the sensitivity of these specimens on fresh samples.

The Alere BinaxNOW® Influenza A & B Card is an immunochromatographic membrane assay that uses highly sensitive monoclonal antibodies to detect influenza type A and B nucleoprotein antigens in respiratory specimens. These antibodies and a control antibody are immobilized onto a membrane support as three distinct lines and combined with other reagents/pads to construct a test strip. This test strip is mounted inside a cardboard, book-shaped hinged test card.

Swab specimens require a sample preparation step, in which the sample is eluted off the swab into elution solution, saline or transport media. Nasal wash/aspirate samples require no preparation. Sample is added to the top of the test strip and the test card is closed. Test results are interpreted at 15 minutes based on the presence or absence of pink-to-purple colored Sample Lines. The blue Control Line turns pink in a valid assay.

Here's a breakdown of the acceptance criteria and the studies that prove the device meets them, based on the provided text:

Device: Alere BinaxNOW® Influenza A & B Card

1. Table of Acceptance Criteria and Reported Device Performance

The document doesn't explicitly state "acceptance criteria" in a structured table format with specific thresholds. However, the performance summary provides quantitative results against a reference standard (Cell Culture/DFA), which implicitly serve as the criteria the device aims to meet. The implicit acceptance criteria would be for the sensitivity and specificity values to be within acceptable ranges for a rapid diagnostic test, generally aiming for high specificity to minimize false positives and reasonable sensitivity. The study results demonstrate these performance characteristics for the device.

Here's a table summarizing the reported device performance for the clinical studies, which can be interpreted as demonstrating the device meets implicit acceptance criteria for sensitivity and specificity:

Implicit Acceptance Criteria (Demonstrated Performance)

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

Prospective Study:

• Sample Size: 846 specimens (nasopharyngeal and nasal swabs).
• Data Provenance: Multi-center clinical studies conducted at a central testing laboratory outside the US during the 2004 respiratory season and at three US trial sites during the 2005-2006 respiratory season.

Retrospective Study:

• Sample Size: 293 frozen clinical samples.
• Data Provenance: Clinical samples collected from symptomatic patients at multiple physician offices, clinics, and hospitals located in the Southern, Northeastern, and Midwestern regions of the United States and from one hospital in Sweden.

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

The document refers to "Cell Culture / DFA" (Direct Fluorescent Antibody) as the comparative method for establishing ground truth. This indicates that the ground truth was established by laboratory testing using established and validated methods, rather than clinical expert consensus. Therefore, the concept of "number of experts" or their "qualifications" in the traditional sense of clinical adjudication by physicians is not directly applicable here. The experts would be the laboratory personnel performing and interpreting the cell culture and DFA, who are presumed to be qualified in these laboratory techniques.

4. Adjudication Method (for the test set)

The adjudication method used for the comparison was against Cell Culture / DFA. This means that discrepancies between the device's results and the Cell Culture / DFA results would be evaluated against the "gold standard" of Cell Culture / DFA without a specified clinical adjudication process detailed in the submission. The text does not mention a 2+1, 3+1, or similar expert adjudication process for discordant results.

5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was done

No, the provided document does not describe an MRMC comparative effectiveness study where human readers' performance with and without AI assistance is evaluated. The study focuses on the standalone performance of the Alere BinaxNOW® Influenza A & B Card compared to laboratory reference methods.

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

Yes, the studies presented are standalone performance studies of the Alere BinaxNOW® Influenza A & B Card. The results show the performance of the device itself (immunochromatographic assay) in detecting influenza antigens, without human interpretation being the primary variable of interest. While human operators interpret the results (presence/absence of pink-to-purple lines), the study assesses the diagnostic accuracy of the test product against the reference standard. The "Reproducibility Study" involved multiple operators interpreting cards, indicating that human interpretation is part of the device's use, but the primary clinical performance studies (sensitivity/specificity vs. Cell Culture/DFA) evaluate the device's diagnostic capability. The "Analytical Sensitivity" section involved 12 different operators interpreting cards, further indicating that the interpretation by human users is part of the device's intended use and evaluation.

7. The type of Ground Truth Used

The primary ground truth used for both prospective and retrospective clinical studies was Cell Culture / DFA (Direct Fluorescent Antibody). This is a widely accepted and established laboratory method for influenza virus detection.

8. The Sample Size for the Training Set

The document does not specify a separate "training set" or its sample size. This is common for rapid diagnostic devices like the Alere BinaxNOW® Influenza A & B Card, which are developed based on established immunological principles and optimized through R&D, rather than being "trained" in the machine learning sense on a distinct dataset. The clinical studies described are validation studies for the finalized device.

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

As noted in point 8, there is no explicit "training set" mentioned in the context of machine learning. Therefore, the establishment of ground truth for a training set is not applicable here. The device's performance was evaluated against the gold standard of Cell Culture/DFA in clinical validation studies.

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The Clearview® Exact II Influenza A & B Test is an in vitro immunochromatographic assay for the qualitative detection of influenza A and B nucleoprotein antigens in nasal swab specimens collected from symptomatic patients. It is intended to aid in the rapid differential diagnosis of influenza A and B viral infections. It is recommended that negative test results be confirmed by cell culture. Negative results do not preclude influenza virus infection and should not be used as the sole basis for treatment or other management decisions.

The Clearview Exact II Influenza A & B Test is an immunochromatographic membrane assay that uses highly sensitive monoclonal antibodies to detect influenza type A and B nucleoprotein antigens in respiratory swab specimens. These antibodies and a control protein are immobilized onto a membrane support as three distinct lines and are combined with other reagents/pads to construct a Test Strip. Nasal swab samples are added to a Coated Reaction Tube to which an extraction reagent has been added. A Clearview Exact II Influenza A & B Test Strip is then placed in the Coated Reaction Tube holding the extracted liquid sample. Test results are interpreted at 10 minutes based on the presence or absence of pink-to-purcle colored Sample Lines. The yellow Control Line turns blue in a valid test.

Here's a breakdown of the acceptance criteria and study information for the Clearview® Exact II Influenza A & B Test, based on the provided 510(k) summary:

1. Table of Acceptance Criteria and Reported Device Performance

The acceptance criteria are implied by the reported performance figures, as the device was deemed "substantially equivalent" which indicates these performance metrics were acceptable to the FDA. The document doesn't explicitly state pre-defined acceptance thresholds, but rather presents the results of the clinical study for evaluation.

Analytical Sensitivity (LOD) - Reported Device Performance:

Analytical Reactivity Testing - Reported Device Performance:

2. Sample size used for the test set and the data provenance

• Sample Size: 478 prospective clinical specimens.
• Data Provenance: Multi-center, prospective clinical study conducted at seven U.S. trial sites during the 2008-2009 respiratory season. Specimens were nasal swabs collected from symptomatic patients.

3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts

The ground truth for the clinical study was established using viral culture. This is a laboratory method and does not involve human experts in the typical "expert consensus" sense for image interpretation or diagnosis. Therefore, information about the number and qualifications of experts in this context is not applicable.

4. Adjudication method (e.g., 2+1, 3+1, none) for the test set

Not applicable, as the ground truth was "viral culture," which is an objective laboratory method rather than expert interpretation requiring adjudication. However, for the 19 samples where the Clearview test was negative for influenza B but viral culture was positive, an investigational RT-PCR assay was used as a follow-up ("Ten (10) of these samples were negative for influenza B by PCR"). This could be seen as a form of secondary verification for discrepant results.

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 device is an immunochromatographic rapid diagnostic test for direct antigen detection, not an AI-powered diagnostic imaging or interpretation tool that assists human readers.

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

Yes, the primary clinical performance study evaluated the device in a standalone manner. The results (sensitivity and specificity) represent the performance of the device itself (Clearview® Exact II Influenza A & B Test) compared to the viral culture gold standard, without human interpretation influence (other than reading the test strip, which is part of the device's intended use and not considered "human-in-the-loop AI assistance"). The reproducibility study also assessed the device's inherent performance characteristics.

7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.)

The ground truth for the clinical study was viral culture.

8. The sample size for the training set

This information is not provided in the 510(k) summary. Given that this is an immunochromatographic assay using monoclonal antibodies, it's a traditional in vitro diagnostic, not a machine learning or AI-driven device that requires a "training set" in the computational sense. The "training" of such a device involves developing and optimizing the biochemical components and manufacturing processes, rather than training an algorithm on a dataset.

9. How the ground truth for the training set was established

Not applicable, as the device is not an AI/ML-based system requiring a training set with established ground truth in the traditional sense. The analytical studies (sensitivity, reactivity, specificity) demonstrate the performance of the developed assay against known viral strains and other microorganisms.

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