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The AmpliVue® Bordetella Assay is an in vitro diagnostic test for the qualitative detection of Bordetella pertussis nucleic acids isolated from nasopharyngeal swab specimens suspected of having respiratory tract infection attributable to Bordetella pertussis.

The AmpliVue® Bordetella Assay utilizes helicase-dependent amplification (HDA) of the insertion sequence IS481 and a selfcontained disposable amplification device that allows for manual evaluation of assay results. The IS48 sequence can also be found in strains of other organisms (i.e., B. holmesii infection may cause clinical illness similar to B. pertussis, and mixed outbreaks involving both B. pertussis and B. holmesii infection have been reported. Additional testing should be performed if necessary to differentiate B. holmesii and B. pertussis. B. bronchiseptica is a rare cause of infection in humans. When clinical factors suggest that B. pertussis may not be the cause of respiratory infection, other clinically appropriate investigation(s) should be carried out in accordance with published guidelines.

Negative results for the AmpliVue® Bordetella Assay do not prection and positive results do not rule out coinfection with other respiratory pathogens. Results from the AmpliVue® Bordetella Assay should be used in conjunction with information obtained during the patient's clinical evaluation as an aid in diagnosis infection and should not be used as the sole basis for treatment or other patient management decisions.

The AmpliVue® Bordetella Assay is intended for use in hospital, reference or state laboratory settings. The device is not intended for point-of-care use.

The AmpliVue® Bordetella Assay combines simple processing, an isothermal amplification technology named helicase-dependent amplification (HDA), and a selfcontained disposable amplicon detection device, for the detection of Bordetella pertussis from nasopharyngeal swabs.

Patient samples are collected using a nasopharyngeal swab and placed into a liguid medium. Fifty microliters (50 µL) of the sample are then transferred to a process buffer that is provided with the kit and mixed. The Process Buffer tubes are heated at 95 °C for 10 minutes. Fifty microliters (50 µL) of the Process Buffer containing sample is added to a reaction tube containing lyophilized mix of HDA reagents. Included in the reaction mix are the isothermal polymerase, helicase and single stranded binding protein. After completion of the HDA reaction the reaction tube is transferred to the amplicon cartridge containing the running buffer. The amplicon cartridge is closed and inserted into the detection chamber. The detection chamber is activated by depressing the detection chamber handle. Upon activation, the reservoir containing the running buffer and the 0.2 mL tube containing the amplicon is punctured and the solutions are wicked to the lateral flow strip.

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

Device Name: AmpliVue® Bordetella Assay

1. Table of Acceptance Criteria and Reported Device Performance

The acceptance criteria are implicitly defined by the reported performance metrics of the clinical study and the analytical performance studies. The clinical study's primary metrics are Positive Percent Agreement (PPA) and Negative Percent Agreement (NPA) compared to a Composite Reference Method. The analytical studies establish limits of detection, inclusivity, and specificity.

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

• Sample Size (Clinical): 842 fresh nasopharyngeal swab specimens were initially collected. After removing 6 invalid specimens, 836 specimens were included in the final analysis.
• Data Provenance: The specimens were collected from patients in the United States (at four locations). The study was prospective, collecting samples in Spring to Summer 2014 (April to August 2014) from patients suspected of having respiratory tract infection attributable to Bordetella pertussis.

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 test set was established using a Composite Reference Method (CRM) involving molecular assays rather than human experts reviewing images or clinical data in an adjudicated manner.

• The CRM included two manufacturer-validated, IS481-targeted real-time PCR assays (PCR1 and PCR2).
• This was followed by bi-directional sequencing from PCR-positive specimens.

Therefore, the concept of "number of experts" and "qualifications of those experts" for establishing ground truth, as typically understood in fields like radiology or pathology, does not directly apply here. The ground truth was based on a laboratory-based molecular diagnostic gold standard.

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

The adjudication method was based on a Composite Reference Method (CRM):

• Specimens were considered positive when bi-directional sequence sequencing results from either comparator PCR assay confirmed the presence of Bordetella pertussis amplicon.
• Specimens were considered negative when neither comparator PCR assay produced Bordetella pertussis amplicon at the end of the 37 cycles.

This is a defined algorithmic (molecular) adjudication process rather than human expert consensus.

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

No, a multi-reader multi-case (MRMC) comparative effectiveness study was not done. This device is an in vitro diagnostic assay for the qualitative detection of nucleic acids, not an imaging device or AI-assisted diagnostic tool that would involve human readers interpreting results.

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

The clinical study evaluated the standalone performance of the AmpliVue Bordetella Assay. The device itself performs the detection and provides a result (visible lines in the cassette window indicating detection or no detection). While human observation is required to read the lines, the assay itself is an "algorithm only" in the sense that its output is directly analogous to a positive/negative result from a fully automated system. The performance metrics (PPA, NPA) reflect this standalone performance against the Composite Reference Method.

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

The ground truth used was a Composite Reference Method (CRM) consisting of:

• Two manufacturer-validated, IS481-targeted real-time PCR assays.
• Bi-directional sequencing for confirmation of PCR-positive specimens.

This is a highly sensitive and specific molecular-based ground truth, often considered a "gold standard" for nucleic acid detection.

8. The sample size for the training set

The document does not report a sample size for a training set. This device uses Helicase-Dependent Amplification (HDA) with a lateral flow strip for detection. It is a molecular diagnostic assay that does not typically involve machine learning with distinct training and test sets in the same way an AI/CADe device would. The development of the assay (primers, probes, reaction conditions) would involve optimization, but this is not typically referred to as a "training set" in this context.

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

As there is no explicit training set discussed in the context of machine learning, the question of how its ground truth was established is not applicable. The underlying components of the assay (primers, probes) are designed based on known biological sequences and Bordetella pertussis characteristics.

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