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The Elecsys CMV IgG assay is an in vitro qualitative test for the detection of IgG antibodies to CMV in human serum, lithium-heparin plasma, K2-EDTA plasma, and K3-EDTA plasma. The test is intended as an aid in the determination of the serological status to CMV in individuals in which a CMV IgG test was ordered, including pregnant women.

Performance characteristics have not been evaluated in immunocompromised or immunosuppressed individuals. This test is not intended for use in neonatal screening or for use at point of care facilities. This test is not intended for use in screening blood and plasma donors.

The electrochemiluminescence immunoassay "ECLIA" is intended for use on cobas e immunoassay analyzers.

Elecsys CMV IgG is a two-step sandwich immunoassay with streptavidin microparticles, biotinylated recombinant CMV-specific antigen labeled with a ruthenium complex and electrochemiluminescence detection. The results are determined using a calibration curve which is instrument-specifically generated by a 2-point calibration and a master curve provided via the reagent bar code. Results greater than or equal to 1.0 U/mL are considered reactive CMV IgG antibody. The test system contains the human serum-based calibrators intended for use with the system.

Elecsys PreciControl CMV lgG contains liquid control serum. The controls are used for monitoring the accuracy of the Elecsys CMV IgG immunoassay.

Note: The reagent and calibrators are packaged together in the Elecsys CMV lgG assay kit, while the associated is packaged separately.

Here's an analysis of the provided text regarding the Elecsys CMV IgG device, structured according to your requested information:

Elecsys CMV IgG Device Acceptance Criteria and Supporting Study

The provided 510(k) summary details the performance evaluation of the updated Elecsys CMV IgG assay.

1. Table of Acceptance Criteria and Reported Device Performance

The document does not explicitly state a quantitative "acceptance criteria" table with specific thresholds (e.g., "sensitivity ≥ X%", "specificity ≥ Y%"). Instead, it describes various studies conducted and concludes that "All performance specifications were met." and "The analytical studies demonstrate that the device is as safe, as effective, and performs as well as the legally marketed predicate device with improved biotin tolerance level up to 1200 ng/mL."

However, based on the studies described, we can infer performance aspects and reported outcomes:

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

• Precision Study:
  • Sample Size: "3 levels of controls and 5 human serum samples per run, 2 runs per day for 21 days." This totals (3 controls + 5 samples) * 2 runs * 21 days = 336 individual measurements (or 21 days of testing on 8 distinct samples).
  • Data Provenance: The text states "human serum samples" and "native human serum pools" for interference studies, implying human origin. No specific country of origin is mentioned. The studies are described as internal performance evaluations, which are typically prospective for the device under development.
• Biotin Interference Study:
  • Sample Size: "three serum samples (negative, positive close to cut-off, positive)" were used, each subjected to "11 dilution steps." This amounts to 3 samples * 11 dilutions = 33 individual sample preparations for testing.
  • Data Provenance: "Native human serum pools" and "a single serum donor." No specific country of origin or retrospective/prospective nature is stated, but it's an analytical study, likely prospective.
• Method Comparison to Predicate:
  • Sample Size: "A total of 280 samples."
  • Data Provenance: Not specified, but likely human serum/plasma samples. The study is analytical and likely prospective.

General Note on Data Provenance: For all studies, the document does not specify the country of origin of the data or explicitly state if the studies were retrospective or prospective, though the nature of these analytical performance studies suggests they were conducted prospectively as part of the device development and validation.

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

The device is an in vitro diagnostic (IVD) for the detection of IgG antibodies to CMV. The "ground truth" for such assays typically relies on established reference methods, a "gold standard" laboratory test result, or classification based on a patient's clinical status (e.g., infected vs. uninfected based on a battery of tests or clinical history).

The provided text does not mention the use of experts (like radiologists) to establish ground truth for any of the studies. For IVDs, "ground truth" is usually analytical (e.g., a sample spiked with a known concentration, or a sample with a confirmed status by a highly sensitive and specific reference method).

4. Adjudication Method for the Test Set

Since the studies described are analytical performance studies for an IVD, and not clinical studies involving interpretation by multiple human readers, there is no mention of an adjudication method like 2+1 or 3+1. Ground truth for these types of studies is typically established by the analytical reference method or preparation of known samples.

5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done

No, a Multi-Reader Multi-Case (MRMC) comparative effectiveness study was not done. This type of study is relevant for imaging devices where human readers interpret results, sometimes with and without AI assistance, to assess the impact of AI on reader performance. The Elecsys CMV IgG is an automated immunoassay, not an imaging device requiring human interpretation of results in the same manner.

6. If a Standalone (i.e., Algorithm Only Without Human-in-the-Loop Performance) Was Done

Yes, the studies described are essentially standalone performance evaluations of the device (Elecsys CMV IgG assay). As an automated immunoassay, the "algorithm" (the assay's chemical reactions and instrument's detection/calculation) provides a result directly. The studies like precision, biotin interference, and method comparison assess the performance of the assay itself without human intervention in the result determination process. The output is a quantitative (U/mL) or qualitative (reactive/non-reactive) result.

7. The Type of Ground Truth Used

The types of "ground truth" implicitly used in the analytical studies are:

• Known Sample Status/Concentration: For the precision study, controls and samples with a certain expected concentration or qualitative status were used.
• Known Biotin Concentration: For the biotin interference study, samples were "spiked with the interfering endogenous substance" (biotin) to known concentrations.
• Predicate Device Results: For the method comparison study, the results from the legally marketed predicate device (Elecsys CMV IgG K131605) served as a comparative "ground truth" to demonstrate equivalence.

The document does not mention pathology, expert consensus, or outcomes data as ground truth, which are more common for diagnostic imaging or clinical decision support AI devices.

8. The Sample Size for the Training Set

The Elecsys CMV IgG assay is an immunoassay, not a machine learning or AI algorithm in the contemporary sense that requires a "training set" for model development. The assay relies on established biochemical reactions (electrochemiluminescence immunoassay "ECLIA"), calibration curves, and reagent lot-specific master curves. Therefore, there is no "training set" in the context of typical AI/ML algorithm development.

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

As there is no "training set" for an AI/ML algorithm, this question is not applicable to the Elecsys CMV IgG device as described. The assay's performance is driven by its chemical formulation, reagents, and instrument calibration, not by a learned model from a training dataset.

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Elecsys CMV IgG:
The Elecsys CMV IgG immunoassay is a test for the in vitro semi-quantitative determination of IgG class antibodies to CMV in human serum, lithium-heparin plasma, K2 -EDTA plasma, and K3 -EDTA plasma. The test is intended for adults, including expectant mothers, as an aid in presumptive diagnosis of CMV infection. Results with this assay are used to indicate past infection with CMV.
The electrochemiluminescence immunoassay "ECLIA" is intended for use on the indicated Elecsys and cobas e immunoassay analyzers.
This test is not FDA cleared for screening blood or plasma donors.
The performance of this assay has not been established for use in a pediatric population, neonates and immunocompromised patients or for use at point of care facilities.
Elecsys PreciControl CMV IgG:
Elecsys PreciControl CMV IgG is used for quality control of the Elecsys CMV IgG immunoassay on the Elecsys and cobas e immunoassay analyzers.

(1) Elecsys CMV IgG is a two-step sandwich immunoassay with streptavidin microparticles, biotinylated recombinant CMV-specific antigen labeled with a ruthenium complex and electrochemiluminescence detection. The results are determined using a calibration curve which is instrument-specifically generated by a 2-point calibration and a master curve provided via the reagent bar code. Results greater than or equal to 1.0 U/mL are considered reactive CMV IgG antibody. The test system contains the human serum-based calibrators intended for use with the system.
(2) Elecsys PreciControl CMV IgG contains liquid control serum based on human serum. The controls are used for monitoring the accuracy of the Elecsys CMV IgG immunoassay.
Note: The reagent and calibrators are packaged together in the Elecsys CMV IgG assay kit, while the associated PreciControl is packaged separately.

The Elecsys CMV IgG Test System was evaluated through a clinical trial to demonstrate its performance characteristics.

1. Acceptance Criteria and Reported Device Performance

The acceptance criteria for the Elecsys CMV IgG Immunoassay are not explicitly stated as numerical targets in the provided text. Instead, the study reports the "Percent Agreement" values (often referred to as sensitivity and specificity for agreement studies) against a reference method (the predicate device, Diamedix Is-CMV IgG).

2. Sample Size and Data Provenance

The study included several cohorts for performance evaluation:

• Routine Cohort: n=500
• Expectant Mother Cohort: n=98
• CMV IgM Positive Cohort: n=119
• Cross-Reactivity Cohort: 249 samples positive for various cross-reactants.

The document does not specify the country of origin for the data or whether it was retrospective or prospective.

3. Number of Experts and Qualifications for Ground Truth

The document does not mention the use of human experts or their qualifications for establishing ground truth for the clinical trial comparing the Elecsys CMV IgG immunoassay with the predicate device. The performance is assessed based on agreement with the predicate device results.

4. Adjudication Method

No adjudication method is mentioned in the provided text, as the comparison is made directly against the predicate device's results.

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

No MRMC comparative effectiveness study involving human readers with and without AI assistance was performed, as this device is an in vitro diagnostic immunoassay, not an AI software intended for human interpretation assistance.

6. Standalone Performance (Algorithm Only)

Yes, a standalone study was performed. The Elecsys CMV IgG Immunoassay's performance metrics (Positive Percent Agreement, Negative Percent Agreement) were directly evaluated against the predicate device's results in various clinical cohorts, representing its standalone performance. Additional analytical performance characteristics like precision, LoB/LoD, hook effect, and cross-reactivity were also evaluated for the Elecsys CMV IgG assay itself.

7. Type of Ground Truth Used

The ground truth for the clinical performance evaluation appears to be established by the results of the predicate device, the Diamedix Is-CMV IgG Test System (K981163). The study reports "Percent Agreement" with this predicate device. For the cross-reactivity study, the ground truth was the known positive status for specific cross-reactants.

8. Sample Size for the Training Set

The document does not explicitly mention a "training set" in the context of an algorithm or machine learning model for the Elecsys CMV IgG Immunoassay. This device is an immunoassay, and its development likely involves laboratory optimization and validation studies, rather than machine learning training sets. Therefore, a sample size for a training set is not applicable or provided.

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

As noted in point 8, the concept of a "training set" and associated ground truth establishment is not typically applicable to the development of an immunoassay like the Elecsys CMV IgG Test System. The document describes standard laboratory validation procedures and clinical performance evaluation against a predicate device.

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