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For in vitro diagnostic use:

Etest is a quantitative technique for the determination of antimicrobial susceptublity of both nonfastidious Gram negative and Gram positive aerobic bacteria, such as Enterobacteriansmassess, fastidious Grain negative and Chain posts ro associal, such as anaerones, Prammonons, Staphyloocws, Gonorous and Haemophius species. The system comprises a predefined and high in and the Streportus, Goldential and Plannylims openion inhibitory concentration (MIC) in ug/ml of gradent which is used to determine the minimals and media by overnight incubation. (Original FDA clearance for Etest - file K913459/A)

This Etest 510(k) submission is for an additional antibiotic i.c. Etest for MIC deemination of This Etest 310(K) Submission is 10.016 - 256 µg/ml with E. faecalis and E. Jaeium (vancomycin-Daptomyen in the MIC faires of over including methicillin resistant strains), coagulase negative Staphylococcus spp. and ß-haemolytic Streptococcus spp.

Etest is a quantitative technique for the determination of antimicrobial susceptublity of both nonfastidious Gram negative and Gram positive aerobic bacteria, such as Enterobacteriansmassess, fastidious Grain negative and Chain posts ro associal, such as anaerones, Prammonons, Staphyloocws, Gonorous and Haemophius species. The system comprises a predefined and high in and the Streportus, Goldential and Plannylims openion inhibitory concentration (MIC) in ug/ml of gradent which is used to determine the minimals and media by overnight incubation.

This document is a 510(k) clearance letter from the FDA for a new Etest® Daptomycin antimicrobial susceptibility test. It does not contain information about acceptance criteria or a study that proves the device meets specific acceptance criteria in the manner you've requested for typical AI/diagnostic device applications.

The provided text is a regulatory clearance document, not a detailed study report. It indicates that the device has been found substantially equivalent to a legally marketed predicate device. The information you're asking for (e.g., sample sizes, expert qualifications, study methodologies, performance metrics like sensitivity/specificity) is usually found in a separate clinical study report, which is typically summarized in the 510(k) submission but not fully detailed in the clearance letter itself.

Therefore, I cannot populate the table or answer the specific questions based only on the text provided because it does not contain that level of detail.

However, I can tell you what is typically expected for such a device in terms of performance and how its substantial equivalence would have been established, based on the nature of antimicrobial susceptibility testing (AST) devices.

For AST devices like the Etest®, "acceptance criteria" usually refer to agreement rates with a reference method (e.g., broth microdilution or agar dilution). The "study" would be a clinical study comparing the Etest® results to these reference methods.

Here's how I would hypothetically complete your request for an AST device, based on common FDA requirements for such submissions, and indicate what is not present in the provided document:

Description of Acceptance Criteria and Study to Prove Device Meets Criteria

Device: Etest® Daptomycin 0.016-256 µg/mL

Intended Use: For in vitro diagnostic use to determine the minimum inhibitory concentration (MIC) of Daptomycin for specific bacterial species (E. faecalis, E. faecium, Staphylococcus spp., Streptococcus spp.).

This 510(k) clearance letter from the FDA indicates that the Etest® Daptomycin has been found substantially equivalent to a legally marketed predicate device. While the provided document does not contain the detailed study results or explicit acceptance criteria, for antimicrobial susceptibility testing (AST) devices, the performance is typically evaluated by comparing results to a recognized reference method.

Hypothetical Acceptance Criteria and Reported Device Performance (Based on typical AST device standards):

Detailed Study Information (Based on common AST device studies – not available in the provided document):

1. Sample size used for the test set and the data provenance:

   • Sample Size: This information is not present in the document. Typically, hundreds to thousands of isolates covering the relevant species and resistance mechanisms would be tested.
   • Data Provenance: This information is not present in the document. Clinical isolates would be collected from diverse geographical regions (e.g., USA, Europe) and could be a mix of retrospective and prospectively collected strains, often including challenge strains with known resistance phenotypes.

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

   • Number of Experts/Ground Truth Method: This information is not present in the document. For AST devices, the "ground truth" is typically established by a reference method (e.g., CLSI-recommended broth microdilution or agar dilution) performed by trained microbiologists, rather than a consensus of experts interpreting images or complex data. The interpretation of the reference method's MIC value into categorical results (S/I/R) is based on established clinical breakpoints (e.g., CLSI guidelines).

3. Adjudication method for the test set:

   • Adjudication Method: This information is not present in the document. Discrepancies between the candidate device and the reference method would typically be adjudicated by repeat testing on both the candidate device and the reference method, or by using an alternative reference method, performed by experienced microbiologists.

4. 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: No. This type of study (MRMC for AI assistance) is not relevant for this device. Etest® is a manual, interpretive test where a trained microbiologist reads the MIC value directly; it is not an AI-powered image analysis or diagnostic support tool. The comparison is between the device's output and a reference method's output, not human performance with/without AI.

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

   • Standalone Performance: Not applicable in the context of AI. Etest® is a manual test and requires a human to interpret the ellipse and read the MIC value. Its performance is directly tied to this human interpretation, albeit a standardized one.

6. The type of ground truth used:

   • Ground Truth Type: This information is not explicitly stated but for AST devices, the ground truth is established by a reference method, such as broth microdilution or agar dilution, performed according to recognized standards (e.g., CLSI M07 guidelines).

7. The sample size for the training set:

   • Training Set Sample Size: Not applicable. Etest® is a phenotypic test method based on diffusion gradients, not a machine learning model that requires a "training set." The methodology is predetermined.

8. How the ground truth for the training set was established:

   • Training Set Ground Truth: Not applicable (as above).

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Antimicrobial Susceptibility Test Discs are for the semi-quantitative susceptibility testing by agar diffusion test procedure of rapidly growing micro-organisms. For Daptomycin these include Staphylococcus aureus (including MRSA), Streptococcus agalactiae, Streptococcus dysgalactiae subsp. equisimilis, Streptococcus pneumoniae, and Enterococcus faecalis (vancomycin-susceptible strains only).

Not Found

Here's an analysis of the provided text regarding the Oxoid Daptomycin Susceptibility Test Disc, focusing on the requested criteria for device acceptance and its supporting study:

The provided document is a 510(k) clearance letter from the FDA for the Oxoid Daptomycin Susceptibility Test Disc. This type of document declares "substantial equivalence" to a legally marketed predicate device, rather than a full de novo approval based on extensive clinical trials for a novel device. Therefore, the information typically available for novel medical devices regarding detailed acceptance criteria, MRMC studies, standalone performance, and ground truth establishment in a study report is not present in this 510(k) clearance letter.

However, based on the nature of antimicrobial susceptibility testing devices, we can infer some general principles and what would typically be expected, even if the specific data isn't in this document.

Inference Based on Standard AST Device Clearance

For Antimicrobial Susceptibility Test (AST) Discs, FDA clearance relies heavily on demonstrating performance (e.g., accuracy against a reference method) for identifying susceptible, intermediate, and resistant categories for specific microorganisms. The "study" here is typically a comparison to a recognized reference method for antimicrobial susceptibility.

1. Table of Acceptance Criteria and Reported Device Performance

Since this is a 510(k) premarket notification for an Antimicrobial Susceptibility Test (AST) Disc, the acceptance criteria and performance are typically related to the accuracy of categorizing isolates as Susceptible (S), Intermediate (I), or Resistant (R) when compared to a gold standard reference method (e.g., broth microdilution or agar dilution).

Inferred Table based on typical AST device clearance for a qualitative/semi-quantitative test:

Explanation:

• Essential Agreement (EA): Agreement within ±1 doubling dilution of the reference method's MIC value; often reflects the zone diameter correlation.
• Categorical Agreement (CA): Agreement in the final S, I, or R category assigned.
• Major Discrepancy (MD): The test device calls an isolate susceptible (S) or intermediate (I) while the reference method calls it resistant (R). (Incorrectly treats a resistant organism).
• Very Major Discrepancy (VMD): The test device calls an isolate resistant (R) while the reference method calls it susceptible (S) or intermediate (I). (Incorrectly treats a susceptible organism, leading to potential treatment failure).
• Minor Discrepancy (mD): One method calls an isolate susceptible (S) or resistant (R) while the other calls it intermediate (I), or vice-versa. (Less critical than MD or VMD but still tracked).

Note: The specific numerical acceptance criteria can vary slightly depending on the drug and organism, but the percentages listed above are broadly representative for AST devices.

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

• Sample Size for Test Set: Not specified in this document. For AST devices, typical studies involve testing a significant number of isolates (e.g., hundreds) for each organism/drug combination, encompassing various resistance mechanisms if relevant. This includes a balanced representation of S, I, and R categories.
• Data Provenance: Not specified in this document. AST studies are often conducted at multiple clinical microbiology laboratories to ensure generalizability. They are typically prospective or use a banked collection of retrospective isolates specifically chosen to represent clinical diversity and resistance profiles relevant to the drug. The country of origin would be global for a company like Oxoid, but specific study sites are not mentioned here.

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

• Number of Experts: Not applicable in the context of AST disc studies in the way it applies to image-based AI. The "ground truth" for AST is not established by expert visual interpretation/consensus.
• Qualifications of Experts: The "experts" in AST are typically trained laboratory personnel following standardized reference testing methodologies (e.g., CLSI or EUCAST guidelines). These individuals perform the reference broth microdilution or agar dilution tests, which serve as the gold standard.

4. Adjudication Method for the Test Set

• Adjudication Method: Not applicable. The "ground truth" in AST is a quantitative measurement (Minimal Inhibitory Concentration - MIC) obtained via a reference method, which then translates into categorical (S, I, R) results. Discrepancies between the investigational device and the reference method are analyzed numerically, not by expert adjudication of conflicting interpretations. Discrepant results, however, are often re-tested by both methods to confirm the initial findings.

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

• MRMC Study: No, highly unlikely. MRMC studies are specific to diagnostic tools where human interpretation of complex images or data is central, and the AI's role is to assist or augment that interpretation. AST discs are a semi-quantitative laboratory test and do not involve human "readers" interpreting images in a way that an MRMC study would be relevant. The performance is assessed against an objective reference method, not against human variability in interpreting the disc zone.

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

• Standalone Performance: Yes, in essence. The entire premise of an AST disc is a standalone performance test. A technician prepares the plate, applies the disc, incubates, and then measures the zone of inhibition. This measurement is then interpreted against predefined breakpoints. The "device performance" relies solely on the physical disc's ability to diffuse the antimicrobial and inhibit bacterial growth, leading to a measurable zone that correlates with susceptibility. There isn't a separate "algorithm" in the AI sense, but rather a set of established breakpoints and measurement standards.

7. The Type of Ground Truth Used

• Ground Truth Type: For AST devices, the ground truth is established by a standardized reference method (e.g., broth microdilution, agar dilution, or a validated automated system) that quantitatively determines the Minimal Inhibitory Concentration (MIC) of the antimicrobial against the specific bacterial isolate. This MIC value is then categorized into Susceptible (S), Intermediate (I), or Resistant (R) based on established clinical breakpoints (e.g., CLSI M100 document). This is a form of objective laboratory measurement rather than subjective expert consensus or pathology.

8. The Sample Size for the Training Set

• Sample Size for Training Set: Not applicable in the typical AI sense. AST discs are not "trained" like machine learning algorithms. Their performance is inherent in the chemical composition of the disc and the diffusion properties of the antimicrobial. Development involves optimizing the drug concentration in the disc and correlating zone diameters with MIC values, which could involve empirical testing on many isolates, but it's not a "training set" for an algorithm.

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

• Ground Truth for Training Set Establishment: Not applicable as described for AI. The "ground truth" for developing the correlation between disc zone diameters and MIC values (which guides optimal disc concentration and breakpoint setting) is established through extensive studies where MICs are determined by a reference method (e.g., broth microdilution) for a wide range of bacterial isolates, and simultaneously, the corresponding zone diameters are measured for the investigational disc. This allows for regression analysis and determination of appropriate zone diameter breakpoints that correlate with the clinical MIC breakpoints.

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