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The CEDIA® DAU AmphAssure Assay is a homogeneous enzyme immunoassay for the in vitro qualitative determination of amphetamines in human urine on automated clinical chemistry analyzers. This device is used as an accessory to immunoassay screening tests to reduce the number of false positive results needing confirmation testing. Measurements are used as an aid in the diagnosis and treatment of amphetamine use or overdose.

The assay provides only a preliminary analytical result. A more specific alternative chemical method must be used to obtain a confirmed analytical result. GCMS is the preferred confirmatory method. Other chemical confirmation methods are available. Clinical consideration and professional judgement should be applied to any drug of abuse test result particularly when preliminary positive test results are used.

The CEDIA® DAU AmphAssure assay uses recombinant DNA technology (US Patent No. 4708929) to produce a unique homogeneous enzyme immunoassay system. This assay is based on the bacterial enzyme B-galactosidase, which has been genetically engineered into two inactive fragments. These fragments spontaneously reassociate to form fully active enzyme that, in the assay format, cleaves a substrate, generating a color change that can be measured spectrophotometrically. The CEDIA DAU AmphAssure assay is a unique test for identification of amphetamines in urine and for the elimination of false positive results due to other cross-reactant substances. Most cross-reactive substances must be present in high concentrations compared to amphetamines in order to give a false-positive result in immunoassay based methods that detect amphetamines. AmphAssure employs the addition of a limited amount of a neutralizing antibody to amphetamine and methamphetamine to neutralize the signal in a true positive sample, without any effect on the signal from a sample containing a high concentration of cross-reactive substance. The neutralizing antibody does not bind the labeled conjugate in the assay, so that its primary effect is to reduce the signal resulting from amphetamines in the sample. Samples containing amphetamines can be distinguished from false-positive samples by the difference in signal before and after addition of the neutralizing antibody. Two analyzer channels are programmed with identical test parameters for the CEDIA AmphAssure assay; reagents without neutralization antibodies are assigned to the first channel, and the reagents with neutralization antibodies are assigned to the second channel. A calculated test (channel three) is programmed to give the difference in results between the first and second channel. Calibrators, controls and patient samples are tested on both channels. The device consists of following: AmphAssure Reagents, AmphAssure Calibrator, Standard, and Control Set.

The provided text does not contain detailed acceptance criteria and supporting study data for the CEDIA® DAU AmphAssure Assay. The document is a 510(k) summary for regulatory clearance, which focuses on demonstrating substantial equivalence to a predicate device rather than presenting a comprehensive study report with quantitative acceptance criteria and performance data.

Here's what can be inferred and what is missing based on your request:

1. A table of acceptance criteria and the reported device performance

• Acceptance Criteria: Not explicitly stated in the document. For an immunoassay like this, acceptance criteria would typically involve sensitivity, specificity, accuracy (e.g., concordance with GC-MS), precision (intra-assay and inter-assay variability), linearity, and cross-reactivity profiles. The document mentions the intended use of reducing false positives, implying that high specificity is a key performance characteristic.
• Reported Device Performance: No specific quantitative performance data is provided in this summary directly comparing the device to acceptance criteria. The document states that the AmphAssure assay is a "unique test for identification of amphetamines in urine and for the elimination of false positive results due to other cross-reactant substances." It also mentions that "Samples containing amphetamines can be distinguished from false-positive samples by the difference in signal before and after addition of the neutralizing antibody." This describes the mechanism intended to improve performance but doesn't present the numerical results of that improvement against a specific criterion.

2. Sample size used for the test set and the data provenance

• Sample Size: Not mentioned.
• Data Provenance: Not mentioned (e.g., country of origin, retrospective or prospective).

3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts

• Number of Experts: Not mentioned.
• Qualifications of Experts: Not mentioned.

4. Adjudication method for the test set

• Adjudication Method: Not mentioned.

5. 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

• MRMC Study: This is a diagnostic immunoassay device, not an imaging device typically associated with "human readers" or "AI assistance" in the context of MRMC studies. Therefore, this type of study is not applicable and not mentioned.

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

• Standalone Performance: The device itself is an automated immunoassay. Its performance is standalone in the sense that it provides a qualitative result (presence or absence of amphetamines) based on the enzymatic reaction and spectrophotometric measurement, without direct human interpretation of complex images or data to generate that initial result. However, the result is "only a preliminary analytical result" and requires "a more specific alternative chemical method... to obtain a confirmed analytical result," usually GC-MS. So, while the assay performs standalone to produce a preliminary result, it's not the definitive standalone diagnostic.

7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.)

• Ground Truth: The document explicitly states: "A more specific alternative chemical method must be used to obtain a confirmed analytical result. GCMS is the preferred confirmatory method." This indicates that Gas Chromatography-Mass Spectrometry (GC-MS) is used as the gold standard or ground truth for confirming the presence of amphetamines.

8. The sample size for the training set

• Training Set Sample Size: Not mentioned. The document describes the technology and mechanism of the assay but does not detail the development or validation studies, which would typically include training set information.

9. How the ground truth for the training set was established

• Ground Truth for Training Set: Since the training set size is not mentioned, the method for establishing its ground truth is also not mentioned. However, it's highly probable that GC-MS would have been used for establishing ground truth for any training or development samples, consistent with its role as the preferred confirmatory method.

In summary, the provided 510(k) summary lacks the detailed study information regarding acceptance criteria, sample sizes, expert involvement, and specific performance metrics that would typically be found in a full study report. It focuses on the device description, intended use, and comparison to a predicate device to demonstrate substantial equivalence, which is the primary goal of a 510(k) submission.

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