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For the qualitative, semi-quantitative and quantitative detection of human IgG antibodies to dsDNA in human serum by enzyme immunoassay, as an aid in the diagnosis systemic lupus erythematosus (SLE). For manual use, or for use with the HyPrep System Plus. For In Vitro Diagnostic Use Only.

For in vitro diagnostic use only.
For the qualitative, semi-quantitative and quantitative detection of IgG antibodies to dsDNA in human serum by enzyme immunoassay.
For use as an aid in the diagnosis of systemic lupus erythematosus (SLE).
For manual use, or for use with the HyPrep System Plus semi-automated fluid handler.

The SeraQuest Anti-dsDNA test is a solid-phase enzyme immunoassay (EIA), which is performed in microwells, at room temperature, in three thirty minute incubations. It has been developed to detect IgG antibodies which are directed against dsDNA, in human serum.

The Calibrators in the SeraQuest Anti-dsDNA test set have been assigned IU/ml values which are traceable to the WHO First International Standard for Anti-Double-Stranded DNA, Wo-80, and Index values which based on an in-house standard anti-dsDNA serum. Test results are reported as IU/ml or as Index values.

Diluted samples are incubated in wells coated with dsDNA antibodies against ds DNA (if present) are immobilized in the wells. Residual sample is eliminated by washing and conjugate (enzyme-labeled antibodies to human IgG) is added and incubated. If IgG antibodies to DSDNA are present, the conjugate will be immobilized in the wells. Residual conjugate is eliminated by washing and draining, and the enzyme substrate is added and incubated. In the presence of the enzyme, the substrate is converted to a yellow end-product which is read photometrically at 405 nm.

Here's an analysis of the provided text to extract information about the acceptance criteria and the study that proves the device meets those criteria:

1. Table of Acceptance Criteria and Reported Device Performance

The document does not explicitly state pre-defined acceptance criteria in terms of specific sensitivity, specificity, or agreement percentages that the SeraQuest Anti-dsDNA device must meet. Instead, the study's performance is presented relative to a predicate device (Shield DIASTAT Anti-dsDNA kit). The de facto acceptance criteria appears to be a demonstration of substantial equivalence to this predicate.

Based on the "Summary of Clinical Testing" and "TABLE 1" which presents the comparative results between the SeraQuest Anti-dsDNA and the predicate Shield DIASTAT Anti-dsDNA, here's a table of the reported device performance:

*Excluding equivocal results.

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

• Sample Size for Test Set: 215 serum specimens.
• Data Provenance: The study was performed "at Quest International, Inc. Miami, FL." The document does not specify the country of origin of the patients from which these specimens were obtained. It is a retrospective study comparing a new device against an existing one using collected specimens.

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

The document does not mention the use of experts to establish a "ground truth" for the test set in the traditional sense (e.g., independent adjudication of disease status). Instead, the comparison is made against a predicate device (Shield DIASTAT Anti-dsDNA kit). The predicate device's results are used as the reference point for calculating relative sensitivity, specificity, and agreement.

However, the context for some samples is mentioned: "{ } Number of patients with clinically diagnosed SLE." This implies a clinical diagnosis made by medical professionals, but the specific number of experts or their qualifications for establishing these clinical diagnoses are not detailed.

4. Adjudication Method for the Test Set

There was no explicit adjudication method described for the test set. The study directly compares the results of the SeraQuest Anti-dsDNA assay with the Shield DIASTAT Anti-dsDNA assay. Discrepancies between the two tests were reported (e.g., 25 specimens equivocal in SeraQuest, 11 equivocal in Shield, 3 positive in SeraQuest and negative in Shield, 5 positive in Shield and negative in SeraQuest), but no adjudication process to resolve these was detailed or used to modify the reported performance metrics. The metrics were calculated based on direct comparison.

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

No, an MRMC comparative effectiveness study was not conducted. This study is an in vitro diagnostic device assessment comparing the performance of two laboratory assays, not a study evaluating human reader performance with or without AI assistance.

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

Yes, a standalone performance assessment was done. The "SeraQuest Anti-dsDNA" device itself is an enzyme immunoassay (a laboratory test) that provides results (qualitative, semi-quantitative, and quantitative detection of IgG antibodies to dsDNA). Its performance as a standalone assay was evaluated by comparing its results directly to those of a predicate assay, not by evaluating human interaction with the device.

7. The Type of Ground Truth Used

The primary "ground truth" for evaluating the SeraQuest Anti-dsDNA device's performance was the results from the predicate device, the Shield DIASTAT Anti-dsDNA kit. This is a comparative study against a legally marketed device.

Secondary information, such as "Number of patients with clinically diagnosed SLE" (mentioned in brackets in Table 1), indicates that some samples had an associated clinical diagnosis (outcomes data/expert consensus for disease status). This clinical diagnosis data helps contextualize the results for some samples but is not the primary "ground truth" against which the device's numerical performance metrics (sensitivity, specificity, agreement) were calculated in this table.

8. The Sample Size for the Training Set

The document does not describe a "training set" in the context of machine learning or algorithm development. This is a traditional in vitro diagnostic device submission for an immunoassay. Therefore, this concept is not applicable here. The assay's parameters would have been developed and optimized prior to this validation study, but no specific "training set" size for that optimization is provided.

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

As noted in point 8, the concept of a "training set" with established ground truth is not applicable to this type of device submission. The device is a laboratory assay, and its performance is validated against a predicate device using a test set of specimens.

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