Search Results

The BinaxNOW® Staphylococcus aureus Test is a qualitative, in vitro immunochromatographic assay for the presumptive identification of Staphylococcus aureus. The test is performed directly on blood culture samples positive for Gram-positive cocci in clusters. The BinaxNOW® Staphylococcus aureus Test is not intended to diagnose Staphylococcus aureus nor to guide or monitor treatment for Staphylococcus aureus infections. Subculturing positive blood cultures is necessary to recover organisms for susceptibility testing and/or differentiation of mixed growth.

The BinaxNOW" Staphylococcus aureus Test is a rapid immunochromatographic membrane assay that uses highly sensitive polyclonal antibodies to detect a Staphylococcus aureus specific protein directly from blood cultures which have been identified as being positive for Gram-positive cocci in clusters. These antibodies and a control antibody are immobilized onto a test strip as two distinct lines and combined with other reagents/pads. This test strip is mounted inside a cardboard, book-shaped hinged test device. Specimens are aliquots from blood cultures which have been identified as positive for Gram-positive cocci in clusters. After the sample is prepared, it is added to the sample pad at the top of the test strip and the device is closed. Results are read at 10 minutes.

Here's a summary of the acceptance criteria and the study details for the BinaxNOW® Staphylococcus aureus Test, based on the provided text:

1. Table of Acceptance Criteria and Reported Device Performance

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

• Sample Size (Clinical Performance Study): 325 blood culture samples.
• Data Provenance: Retrospective and/or prospective (not explicitly stated if combined or separate, but clinical performance was "established in a multicenter clinical study conducted in 2008-09"). The data originated from three geographically-diverse hospital laboratories within the US.

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

• The document states that the BinaxNOW® Staphylococcus aureus Test performance was compared "to standard methods used routinely by the testing laboratories." It does not specify the number of experts or their qualifications for establishing the ground truth, but implies it was based on established laboratory protocols and potentially expert interpretation where applicable for "standard methods." The reference method essentially serves as the "ground truth."

4. Adjudication Method for the Test Set

• The document does not describe a specific adjudication method (like 2+1 or 3+1). The comparison was made against "standard methods used routinely by the testing laboratories," suggesting that the results from these standard methods were taken as the truth without further expert adjudication beyond the routine lab procedures.

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

• No, a multi-reader multi-case (MRMC) comparative effectiveness study was not done. This device is an in vitro diagnostic (IVD) assay, not an AI-assisted diagnostic tool for human readers. Its performance is evaluated independently or against a reference method.

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

• Yes, the clinical performance study evaluated the standalone performance of the BinaxNOW® Staphylococcus aureus Test. It's an immunochromatographic assay that provides a direct result, not an aid to a human reader. Its results were compared directly to the reference method without human interpretation as part of the device's output.

7. The Type of Ground Truth Used

• The ground truth for the clinical performance study was established using "standard methods used routinely by the testing laboratories." For an IVD like this, this typically refers to recognized microbiological culture and identification techniques, which are considered the gold standard for bacterial identification.

8. The Sample Size for the Training Set

• The document does not explicitly mention a "training set" in the context of device development or clinical trials. This is common for rapid immunochromatographic assays, where development involves analytical studies (reactivity, specificity, sensitivity) and then validation in clinical samples. The "training set" concept is more pertinent to machine learning algorithms.

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

• As a "training set" is not explicitly mentioned for this type of device, the method for establishing its ground truth is not applicable or described in the provided text. The analytical studies (reactivity, specificity) used well-characterized bacterial strains (e.g., ATCC, NARSA strains) for which the identity was already known, serving a similar function to establishing "ground truth" for those specific analytical evaluations.

Ask a specific question about this device

Staphytect Plus, and Dryspot Staphytect Plus are latex agglutination tests for the differentiation of Staphylococci which possess clumping factor, Protein A, and certain capsular polysaccharides found in MRSA strains, from those which do not.

Staphytect Plus, and Dryspot Staphytect Plus are latex agglutination tests.

Since the provided text is a 510(k) clearance letter for the Staphytect Plus/Dryspot Staphytect Plus device, it primarily focuses on the FDA's determination of substantial equivalence to a predicate device. This type of regulatory document does not typically contain detailed information about the acceptance criteria, specific study design, or performance metrics in the way that would be found in a clinical study report or a premarket approval (PMA) application.

Therefore, many of the requested details cannot be extracted directly from this document. However, I can provide what can be inferred or directly stated based on the nature of a 510(k) submission.

Here's an attempt to answer your questions based on the provided text, with clear indications where information is not available:

Device Name: Staphytect Plus / Dryspot Staphytect Plus

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

2. Sample size used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective)

• Sample Size: Not available in this document.
• Data Provenance: Not available in this document. A 510(k) submission would typically include a summary of data, but the clearance letter itself doesn't contain these specifics. The manufacturer (Oxoid Limited) is based in England, which might suggest data could originate from there or other regions where the company conducted testing.

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

• Number of Experts: Not available in this document.
• Qualifications of Experts: Not available in this document.

4. Adjudication method (e.g. 2+1, 3+1, none) for the test set

• Adjudication Method: Not available in this document.

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 Done: Not applicable. This device is a latex agglutination test for bacterial differentiation, not an AI-assisted diagnostic imaging or interpretation tool. Therefore, human readers or AI assistance in that context are not relevant.

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

• Standalone Performance: Not applicable. This device is a laboratory reagent-based test. Its performance is inherent to the chemical/biological reaction, not an algorithm.

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

• Type of Ground Truth: Not explicitly stated in the letter. For a bacterial differentiation test, the ground truth would typically be established by:
  • Culture and definitive identification methods: Such as biochemical tests, molecular methods (e.g., PCR), or mass spectrometry (e.g., MALDI-TOF MS) to confirm the presence of Staphylococcus species and the specific factors (clumping factor, Protein A, certain capsular polysaccharides).
  • Reference laboratory standards: Comparison to established methods or results from validated reference laboratories.

8. The sample size for the training set

• Training Set Sample Size: Not applicable/not available. This is a traditional in vitro diagnostic test, not a machine learning/AI model that typically uses a training set. The development of such a test involves extensive R&D and optimization, but not in the "training set" sense of AI.

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

• Ground Truth for Training Set: Not applicable. As noted above, typical AI/ML training concepts do not apply to this type of device. The development process would establish optimal reagent concentrations and reaction conditions based on known positive and negative controls and clinical isolates, but this is a different paradigm than "training" an algorithm.

Summary of what is known from the document regarding regulatory acceptance:

• Regulatory Class: I
• Product Code: JWX
• FDA Determination: Substantially equivalent to devices marketed prior to May 28, 1976.
• Indication for Use: Latex agglutination tests for the differentiation of Staphylococci which possess clumping factor, Protein A, and certain capsular polysaccharides found in MRSA strains, from those which do not.
• CLIA Complexity: The device may require CLIA complexity categorization (applicant advised to contact CDC).

This document serves as the FDA's clearance notice, confirming that the manufacturer has successfully demonstrated substantial equivalence based on the data submitted in their 510(k) application. It does not provide the detailed scientific and clinical evidence itself.

Ask a specific question about this device

Ask a specific question about this device