(126 days)
The Diagnostic Hybrids, Inc. DFA (Direct Fluorescent Antibody) Respiratory Virus Screening & ID Kit is intended for the qualitative detection and identification of the common respiratory viruses, Influenza A, Influenza B, Respiratory Syncytial Virus (RSV), Adenovirus, Parainfluenza 1, Parainfluenza 2 and Parainfluenza 3 directly in prepared patient specimens and in cell cultures following viral amplification. Specimens found to be negative after examination of the direct specimen result must be confirmed by cell culture.
The subject device consists of a series of reagents that are used to screen for and identify 7 common respiratory viruses using murine monoclonal antibodies directly labeled with fluorescein (Direct Fluorescence Assay or DFA) and which are specific for antigenic determinants found on each virus. The subject device provides the following materials: Respiratory Virus DFA Screening Reagent, Seven Individual DFA Solutions, Antigen Control Slides, Normal Mouse Gamma Globulin DFA Reagent, Wash Solution Concentrate, and Mounting Fluid. The device is used for direct testing of patient specimens (aspirates, washes or swabs from the nasopharyngeal area) and cell culture testing of specimens.
This document describes the Diagnostic Hybrids, Inc. DFA (Direct Fluorescent Antibody) Respiratory Virus Screening & ID Kit, which is intended for the qualitative detection and identification of 7 common respiratory viruses. The study aims to demonstrate substantial equivalence to a predicate device, the Bartels Viral Respiratory Screening and Identification Kit and the Diagnostic Hybrids, Inc. IFA Respiratory Viruses Screening and Identification Kit (manufactured by Trinity Biotech, Plc). The primary difference between the new device and the predicate is the use of Direct Fluorescent Antibody (DFA) methodology versus Indirect Fluorescent Antibody (IFA).
Here's an analysis of the provided information concerning acceptance criteria and supporting studies:
1. Table of Acceptance Criteria and Reported Device Performance
The provided text does not explicitly state numerical acceptance criteria for sensitivity, specificity, or agreement rates. Instead, the general acceptance criterion appears to be "substantially equivalent" to the predicate device.
| Performance Metric | Acceptance Criteria (Implicit) | Reported Device Performance (Relative to Predicate) |
|---|---|---|
| Specificity | No cross-reactivity with other viruses or organisms. Must be at least equivalent to the predicate assay. | No cross-reactivity found with any of the 92 potentially cross-reacting organisms, even at twice the normal antibody concentrations. This demonstrates at least equivalent specificity to the predicate. |
| Clinical Performance (Overall Equivalence) | Yields results substantially equivalent to the predicate assay. | Clinical evaluations confirmed that the DFA Respiratory Virus Screening & ID Kit yields results substantially equivalent to the predicate kit. |
2. Sample Size Used for the Test Set and Data Provenance
The exact sample size for the clinical test set is not explicitly stated in numerical terms. The document mentions "clinical specimens" and "specimen data generated by each Study Site."
- Sample Size: Not explicitly quantified. The phrase "clinical specimens" in two study sites suggests a collection of patient samples.
- Data Provenance: Retrospective (clinical specimens were tested), source is two unnamed "study sites" (Appendices 1 and 2, which are not provided in the input). No country of origin is specified, but given the context of FDA submission, it's likely to be the USA.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
The document does not specify the number of experts or their qualifications for establishing the ground truth of the test set. The ground truth appears to be established by the results of the predicate device.
4. Adjudication Method for the Test Set
The document does not describe any specific adjudication method. The comparison is made directly between the results of the subject assay and the predicate assay on the same specimens.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done
No, an MRMC comparative effectiveness study involving human readers is not mentioned. The study focuses purely on comparing the performance of the new DFA device against the predicate IFA device. The advantage of DFA is stated as "less than half the time and with fewer reagents and steps," which is an operational efficiency claim rather than improved human effectiveness with AI assistance.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Was Done
Yes, this appears to be a standalone performance study. The device is a diagnostic kit (reagents and procedures) that is compared to another diagnostic kit. The "performance" being evaluated is the accuracy of the DFA test results compared to the IFA test results, not an AI algorithm.
7. The Type of Ground Truth Used
The ground truth for the clinical studies was established using the predicate device's results. The study directly compared the subject assay's results to those of the predicate assay. For the cross-reactivity studies, the ground truth was based on known properties of 92 potentially cross-reacting organisms obtained from the American Type Culture Collection, where the absence of cross-reactivity was expected.
8. The Sample Size for the Training Set
There is no mention of a "training set" in the context of this device. This is a diagnostic kit (reagents and procedures), not an AI algorithm that requires a training set. The "studies" described are validation studies.
9. How the Ground Truth for the Training Set Was Established
As there is no training set for this type of device, this question is not applicable.
§ 866.3330 Influenza virus serological reagents.
(a)
Identification. Influenza virus serological reagents are devices that consist of antigens and antisera used in serological tests to identify antibodies to influenza in serum. The identification aids in the diagnosis of influenza (flu) and provides epidemiological information on influenza. Influenza is an acute respiratory tract disease, which is often epidemic.(b)
Classification. Class I (general controls). The device is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in § 866.9.