(157 days)
CMVgen is an in vitro diagnostic, rapid latex particle agglutination test for the qualitative and semiquantitative determination of total antibodies (IgG and IgM) to cytomegalovirus (CMV) in human serum or plasma (EDTA) to determine prior exposure to cytomegalovirus. This product is not FDA cleared for use in screening blood or plasma (EDTA) donors.
CMVgen is an in vitro diagnostic, rapid latex particle agglutination test for the qualitative and semiquantitative determination of total antibodies (IgG and IgM) to cytomegalovirus (CMV) in human serum or plasma (EDTA) to determine prior exposure to cytomegalovirus.
The provided text describes the CMVgen device, an in vitro diagnostic test for Cytomegalovirus (CMV) antibodies. However, the document does not explicitly state "acceptance criteria" for the device's performance. Instead, it presents performance data from method comparison studies and a reproducibility study.
Here's an analysis of the provided information, structured to address your questions based on the available text:
Acceptance Criteria and Device Performance
The document does not explicitly define "acceptance criteria" with numerical thresholds for sensitivity, specificity, or other metrics. Instead, it reports the performance of CMVgen against commercially available predicate or reference tests. We can infer that the reported sensitivities were considered acceptable for the 510(k) clearance process.
Table of Performance (Inferred from Study Results)
| Performance Metric | Study 1: Against a commercially available total antibody test | Study 2: Against a commercially available IgG EIA test (in organ transplant recipients) | Reproducibility |
|---|---|---|---|
| Reported Device Performance: | |||
| Sensitivity | 97.5% | 91.1% | Not applicable |
| Reproducibility | Not applicable | Not applicable | 100% |
Study Details
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Sample sizes used for the test set and the data provenance:
- Study 1: 165 serum samples.
- Provenance: Performed at UMMC Clinical Microbiology Laboratories (Massachusetts). This indicates data from the USA and is retrospective as it refers to collected samples being evaluated.
- Study 2: 131 serum samples.
- Provenance: Performed at Cambridge University (U.K.). This indicates data from the UK. Ninety of these samples were collected from 31 organ transplant recipients who had experienced either a primary CMV infection or a reactivation of CMV post-transplant. This suggests a mix of retrospective and potentially prospective collection for the transplant recipient cohort, though the overall study presented is an evaluation of existing samples.
- Reproducibility Study: Panels of 10 serum and plasma samples.
- Provenance: Not explicitly stated, but likely conducted by the manufacturer or a collaborating lab.
- Study 1: 165 serum samples.
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Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
The studies described are method comparison studies and a reproducibility study. The "ground truth" was established by commercially available, established assays (a "commercially available total antibody test" and a "commercially available IgG EIA test"), not by independent expert interpretation for each case. Therefore, the concept of "number of experts" or their qualifications for establishing ground truth in this context is not directly applicable. -
Adjudication method for the test set:
Not applicable, as ground truth was established by reference assays, not by subjective expert review requiring adjudication among multiple readers. -
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, this is not an MRMC study. The CMVgen device is an in vitro diagnostic (IVD) assay, not an AI or imaging-based device requiring human reader interpretation or assistance. Therefore, this question is not relevant to the provided information. -
If a standalone (i.e., algorithm only without human-in-the-loop performance) was done:
Yes, the performance presented for CMVgen is its standalone performance as an assay. It is inherently an "algorithm only" in the sense of a chemical/biological reaction and readout, without human-in-the-loop performance influencing the assay's result. The human reads the result of the assay. -
The type of ground truth used:
The ground truth was established by comparison to commercially available, established assays (reference tests). This is a common method for validating new IVD assays. -
The sample size for the training set:
The document does not mention a "training set" in the context of machine learning or AI. For IVD assays, products are typically developed and optimized using various samples, but these are not usually formally designated as "training sets" in the same way as in AI/ML validation. The samples mentioned (165 and 131 samples) are referred to as evaluation or test samples for performance assessment. -
How the ground truth for the training set was established:
Not applicable, as there is no explicitly defined "training set" as understood in AI/ML, nor is there a described process for establishing ground truth for such a set. Development and optimization of an IVD assay would involve a range of known positive and negative samples, but the method for establishing their "truth" is not detailed in this summary. It would typically involve clinical diagnosis, other gold-standard assays, or well-characterized patient cohorts.
§ 866.3175 Cytomegalovirus serological reagents.
(a)
Identification. Cytomegalovirus serological reagents are devices that consist of antigens and antisera used in serological tests to identify antibodies to cytomegalovirus in serum. The identification aids in the diagnosis of diseases caused by cytomegaloviruses (principally cytomegalic inclusion disease) and provides epidemiological information on these diseases. Cytomegalic inclusion disease is a generalized infection of infants and is caused by intrauterine or early postnatal infection with the virus. The disease may cause severe congenital abnormalities, such as microcephaly (abnormal smallness of the head), motor disability, and mental retardation. Cytomegalovirus infection has also been associated with acquired hemolytic anemia, acute and chronic hepatitis, and an infectious mononucleosis-like syndrome.(b)
Classification. Class II (performance standards).