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For in vitro diagnostic use with the IMMULITE® 2000 Analyzer -- for the quantitative measurement of allergen-specific IgE in human serum, as an aid in the clinical diagnosis of IgE-mediated allergic disorders. The test results are to be used in conjunction with clinical findings and other laboratory tests.

IMMULITE® 2000 3gAllergy™ Specific IgE is a solid-phase, two-step, chemiluminescent immunoassay that exploits liquid phase kinetics in a bead format. It represents a significant advance over conventional methods relying on allergens attached to a solid-phase support, such as a paper disk. The allergens are covalently bound to a soluble polymer matrix, which in turn is labeled with a ligand. The use of an amino acid co-polymer amplifies the amount of allergen that the matrix can support. Incubation Cycles: 2 × 30 minutes.

The Siemens Healthcare Diagnostics Inc. IMMULITE® 2000 3gAllergy™ Specific IgE Assay is intended for the quantitative measurement of allergen-specific IgE in human serum, to aid in the clinical diagnosis of IgE-mediated allergic disorders.

1. Acceptance Criteria and Reported Device Performance

The provided document does not explicitly state pre-defined acceptance criteria for precision, linearity, or clinical performance in numerical terms for the new allergens to be cleared. However, the study results are presented to demonstrate acceptable analytical performance and comparability to clinical data.

Precision:
Precision was evaluated by calculating the intra-assay (Within-Run) and inter-assay (Total) percent coefficients of variation (%CV) for positive samples. The reported CVs are generally low, with within-run CVs mostly below 5% (with some exceptions like Positive #4 for Lime at 9.15%) and total CVs mostly below 6% (with some exceptions like Positive #4 for Lime at 11.47%). The document states that "acceptable analytical performance including precision" was demonstrated, implying these values met internal or regulatory expectations.

Linearity:
Linearity was assessed by comparing observed to expected data from 2-fold serial dilutions. The regression equations show slopes very close to 1 and intercepts close to 0, with 95% confidence intervals for both slope and intercept generally containing 1 and 0 respectively. This indicates good linearity across the tested range. The document states "acceptable analytical performance including linearity" was demonstrated.

Specificity (Inhibition Studies):
Specificity was confirmed through competitive inhibition testing. The acceptance criterion was explicitly stated as achieving a target % inhibition of 50% for the highest inhibitor concentration tested. The reported performance is that this target was met for all tested allergens.
Additional inhibition studies for cross-reactivity used a criterion of results being below 9.9% for specific allergens when tested with unrelated allergen extracts. The reported performance states that results were below 9.9% for Asparagus, Blueberry, Cauliflower, and Perch when tested with unrelated extracts, and for Apricot, Chili Pepper, Chub Mackerel, Ginger, Lime, and Whey.

Clinical Performance:
The document presents an agreement rate with clinical data. The acceptance criteria for clinical performance are implicitly defined by the reported lower and upper confidence intervals, which fall within generally accepted ranges for such diagnostic assays.

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

• Precision Test Set: The number of samples varied. For each allergen, "two aliquots of each test sample in two runs per day on 20 different days" were used for Positive 1-3. For Positive #4, "two aliquots of each test sample in two runs per day on 10 different days" were used. Three allergen lots were tested using three positive and one negative sample. The allergen specificity results involved a single serum sample or pool of sera for inhibition studies.
• Linearity Test Set: For each allergen, two samples were diluted in 2-fold serial dilutions to 5 levels, plus the undiluted sample. The "N" in the regression table (e.g., 11 or 12) likely refers to the number of data points used for regression analysis, representing these diluted samples.
• Specificity (Inhibition) Test Set: A single serum sample or pool of sera was used for each specific allergen, tested with various concentrations of inhibitor extract. For cross-reactivity, one positive sample with three unrelated allergen extracts was used.
• Clinical Performance Test Set: A total of 1,398 serum samples were tested: 396 from clinically diagnosed atopic individuals and 1,002 from non-atopic individuals.
• Data Provenance: The document does not explicitly state the country of origin for the clinical or analytical samples. The study appears to be retrospective, as it refers to "serum samples from clinically diagnosed atopic and non-atopic individuals" and "clinical documentation of presence or absence of signs, symptoms and other diagnostic evidence of allergen sensitivity."

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

N/A. For this IVD device, ground truth for clinical performance was established by "clinical documentation of presence or absence of signs, symptoms and other diagnostic evidence of allergen sensitivity." It does not involve human readers/experts evaluating images or other subjective data, but rather diagnoses and other medical records.

4. Adjudication Method for the Test Set

N/A. Ground truth for clinical performance was based on "clinical documentation." There is no mention of an adjudication method among multiple experts for establishing this ground truth, as it's based on existing clinical diagnoses and evidence.

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

No, an MRMC comparative effectiveness study was not done. This is not applicable to a standalone immunoassay device like the IMMULITE® 2000 3gAllergy™ Specific IgE Assay, which performs an automated quantitative measurement and does not involve human readers interpreting results in the same way as, for example, diagnostic imaging studies.

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

Yes, the studies described are essentially "standalone" performance studies for the IMMULITE® 2000 3gAllergy™ Specific IgE Assay. The device performs the quantitative measurement of allergen-specific IgE without human intervention in the analytical process. The results are then compared to "clinical documentation," but the device's measurement itself is autonomous.

7. The Type of Ground Truth Used

• Analytical Performance (Precision, Linearity): Ground truth is based on the inherent properties of the quality control materials (e.g., known concentrations for linearity, statistical properties for precision).
• Specificity (Inhibition): Ground truth for inhibition is the expected biochemical reaction demonstrating specific binding. Ground truth for cross-reactivity is established by using known unrelated allergens and expecting a low response.
• Clinical Performance: The ground truth for the clinical performance study was based on clinical diagnoses and "other diagnostic evidence of allergen sensitivity" from medically documented cases (e.g., atopic or non-atopic individuals). This is considered outcomes data or existing clinical records.

8. The Sample Size for the Training Set

N/A. This document describes the validation of a laboratory diagnostic assay, not an AI/machine learning algorithm that typically requires a distinct training set. The assay's "design" is based on established immunochemistry principles rather than training on a dataset.

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

N/A. As this is not an AI/ML algorithm, there is no "training set" in that context.

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