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VITEK 2 AST-Gram Negative Cefazolin is designed for antimicrobial susceptibility testing of Gram-negative bacilli and is intended for use with the VITEK 2 Systems as a laboratory aid in the determination of in vitro susceptibility to antimicrobial agents.

VITEK 2 AST-Gram Negative Cefazolin (≤1-≥32 µg/mL) is a quantitative test. Testing is indicated for Enterobacterales (from infections other than uncomplicated UTI) as recognized by the FDA Susceptibility Test Interpretive Criteria (STIC).

VITEK 2 AST-Gram Negative Cefazolin (≤1-≥32 µg/mL) has demonstrated acceptable performance with the following organisms:

Enterobacterales (Escherichia coli, Proteus mirabilis, Klebsiella pneumoniae, Klebsiella oxytoca, Citrobacter koseri)

The VITEK 2 Gram Negative Susceptibility Card is intended for use with the VITEK 2 Systems in clinical laboratories as an in vitro test to determine the susceptibility of clinically significant aerobic Gram- negative bacilli to antimicrobial agents when used as instructed.

The principle of the VITEK® 2 AST cards is based on the microdilution minimum inhibitory concentration (MIC) technique reported by MacLowry and Marsh (1) and Gerlach (2). The VITEK® 2 AST card is essentially a miniaturized, abbreviated and automated version of the doubling dilution technique (3).

Each VITEK® 2 AST card contains 64 wells. A control well which only contains microbiological culture media is resident on all cards. The remaining wells contain premeasured portions of a specific antibiotic combined with culture media. The bacterial or yeast isolate to be tested is diluted to a standardized concentration with 0.45 – 0.5% saline before being used to rehydrate the antimicrobial medium within the card. The VITEK® 2 System automatically fills, seals and places the card into the incubator/reader. The VITEK® 2 Compact has a manual filling, sealing and loading operation. The VITEK® 2 Systems monitor the growth of each well in the card over a defined period of time. At the completion of the incubation cycle, a report is generated that contains the MIC value along with the interpretive category result for each antibiotic contained on the card.

VITEK® 2 AST-GN Cefazolin has the following concentrations in the card: 1, 2, and 8 (equivalent standard method concentration by efficacy in µg/mL).

The provided text describes the acceptance criteria and a study proving the device meets these criteria for the VITEK 2 AST-Gram Negative Cefazolin antimicrobial susceptibility testing system.

Here's a breakdown of the requested information:

1. Table of Acceptance Criteria and Reported Device Performance

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The VITEK® COMPACT PRO is intended for the automated quantitative and/or qualitative antimicrobial susceptibility testing of isolated colonies for most clinically significant aerobic Gram-negative bacilli, Staphylococcus spp., Enterococcus spp., Streptococcus spp., and yeast.

The VITEK® COMPACT PRO is also intended for the automated identification of most clinically significant anaerobic organisms and Corynebacterium species, fermenting and nonfermenting Gram-negative bacilli, Gram-positive organisms, fastidious organisms, and yeasts and yeast-like organisms.

The VITEK® COMPACT PRO instrument is an automated instrument designed for use in low-to medium-range applications in both Clinical and Industry laboratories. The instrument performs sample well filling, incubation, and optical readings. The VITEK® COMPACT PRO instrument is a two-step automated instrument for:

• Hydrating reagents with sample inoculum
• Pre-processing cards, incubating cards, and continuous reading for growth

The VITEK® 2 Systems Software receives the instrument optical readings and performs analysis. The instrument then ejects the completed reagent card into the waste area for disposal.

The system includes a VITEK® COMPACT PRO instrument with an internal computer, monitor, keyboard, mouse, handheld barcode scanner, and USB hub. The software provided with the internal computer includes analysis and limited data management programs. A bidirectional computer interface (BCI) may transfer results automatically to the user's laboratory information system (LIS).

A Quality Control System is available to track the quality control results of the test cards. The Advanced Expert System™ (Clinical Use) is available to provide online, systematic validation of results and interpretation of resistant phenotypes found during susceptibility testing.

The provided text describes the regulatory clearance of a medical device, the VITEK® COMPACT PRO, and its performance evaluation. However, it does not explicitly define "acceptance criteria" in a table format with specific numerical targets. Instead, it details the results of various performance tests as evidence that the device meets acceptable standards, primarily by demonstrating substantial equivalence to a predicate device.

Here's an interpretation of the acceptance criteria and study that can be extracted from the provided information:

Interpretation of Acceptance Criteria and Study Design:

The VITEK® COMPACT PRO is an automated antimicrobial susceptibility testing system. The core of its acceptance criteria and the study proving it meets these criteria relies on demonstrating substantial equivalence to a previously cleared VITEK® 2 System (N50510 Supplement S082). This means the new device must perform comparably to the predicate device across various metrics.

1. Table of Acceptance Criteria (Inferred) and Reported Device Performance:

Since explicit acceptance criteria are not tabulated with thresholds, they are inferred from the reported performance, with the implicit criterion being "comparable to or better than the predicate device."

2. Sample Sizes Used for the Test Set and Data Provenance:

• QC Testing: Each of the 13 quality control organisms was tested at least twenty times. This testing was conducted at "at least three of the clinical evaluation trial sites."
• Reproducibility: Isolates were tested in triplicate for three trial sites. Individual test sets were selected for each antimicrobial, with each set including a minimum of 10 strains (at least 2 with on-scale results).
• Clinical Performance Evaluation: "Representative, clinically relevant strains" were tested. Each strain was tested one time with both the VITEK® COMPACT PRO and the VITEK® 2.
• Data Provenance: The document states testing was done at "at least three of the clinical evaluation trial sites" for QC and "three trial sites" for reproducibility. The country of origin for these sites is not specified, but bioMérieux Inc. is located in Hazelwood, Missouri, USA, implying the studies were likely conducted in the US. The studies appear to be prospective as they involve new testing of isolates for performance evaluation.

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

This information is not explicitly stated in the provided text. The ground truth for the clinical performance evaluation was established by comparing the VITEK® COMPACT PRO's results against the VITEK® 2 System's results (N50510 Supplement S082), which implicitly serves as the "expert consensus" or "reference method" in this context. The document does not describe a separate human expert panel for adjudication or ground truth establishment the way it might for an AI imaging device.

4. Adjudication Method for the Test Set:

Not applicable in the traditional sense of human expert adjudication. The comparison was directly between the new device (VITEK® COMPACT PRO) and the predicate device (VITEK® 2 System) for MICs and interpretations (S/SDD/I/R). There's no mention of a 2+1 or 3+1 human expert adjudication process.

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, an MRMC study was not done. This device is an automated in vitro diagnostic instrument, not an AI-assisted imaging device for human interpretation. The comparison is machine-to-machine (new instrument vs. predicate instrument).

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

Yes, the primary performance evaluation was a standalone "algorithm only" (instrument only) performance comparison. The VITEK® COMPACT PRO (device under test) generated MICs and interpretations, and these were directly compared to those generated by the predicate VITEK® 2 System. Human "in-the-loop" performance is not relevant for the core function of this automated susceptibility system in the context of its performance study.

7. The type of ground truth used:

The ground truth for the clinical performance evaluation was the MIC results and categorical interpretations (S/SDD/I/R) obtained from the legally marketed predicate device, the VITEK® 2 System (N50510 Supplement S082). This serves as the reference method against which the new device's performance is measured.

8. The Sample Size for the Training Set:

The document does not discuss a separate "training set" in the context of device development or performance evaluation. This is not an AI/ML device where a distinct training dataset is typically used. The development process likely involved internal verification and validation, but the reported studies (QC, Reproducibility, Clinical Performance) are essentially testing/validation datasets.

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

Not applicable, as no explicit training set for an AI/ML algorithm is described.

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VITEK 2 AST-Yeast Voriconazole is designed for antifungal susceptibility testing of Candida species and is intended for use with the VITEK 2 and VITEK 2 Compact Systems as a laboratory aid in the determination of in vitro susceptibility to antifungal agents. VITEK 2 AST-Yeast Voriconazole is a quantitative test. Voriconazole has been shown to be active against most strains of the microorganisms listed below, according to the FDA label for this antifungal.

Active in vitro and in clinical infections: Candida krusei Candida parapsilosis Candida tropicalis

The VITEK 2 Fungal Susceptibility Card is intended for use with the VITEK 2 Systems in clinical laboratories as an in vitro test to determine the susceptibility of clinically significant yeasts to antifungal agents when used as instructed.

The principle of the VITEK® 2 AST cards is based on the microdilution minimum inhibitory concentration (MIC) technique. The VITEK® 2 AST card is essentially a miniaturized, abbreviated and automated version of the doubling dilution technique. Each VITEK® 2 AST card contains 64 wells. A control well which only contains microbiological culture media is resident on all cards. The remaining wells contain premeasured portions of a specific antibiotic combined with culture media. The bacterial or yeast isolate to be tested is diluted to a standardized concentration with 0.45-0.5% saline before being used to rehydrate the antimicrobial medium within the card. The VITEK® 2 System automatically fills, seals and places the card into the incubator/reader. The VITEK® 2 Compact has a manual filling, sealing and loading operation. The VITEK® 2 Systems monitor the growth of each well in the card over a defined period of time. At the completion of the incubation cycle, a report is generated that contains the MIC value along with the interpretive category result for each antibiotic contained on the card.

VITEK® 2 AST-YS Voriconazole has the following concentrations in the card: 0.03125, 0.125, 0.25, 1, and 2 (equivalent standard method concentration by efficacy in ug/mL).

The provided FDA 510(k) summary describes the VITEK® 2 AST-Yeast Voriconazole device, which is an antimicrobial susceptibility test system.

Here's an analysis of the acceptance criteria and the study that proves the device meets them:

1. Table of Acceptance Criteria and Reported Device Performance:

The acceptance criteria are implicitly derived from the FDA Class II Special Controls Guidance Document: Antimicrobial Susceptibility Test (AST) Systems and are presented through "Essential Agreement" (EA) and "Category Agreement" (CA) performance metrics, along with error rates. The table below summarizes the reported performance for each microorganism. The specific acceptance thresholds for EA and CA are not explicitly stated as numerical percentages (e.g., >90% EA, >90% CA) with the exception of the individual error types (VME, ME, mE) having specified maximum allowable percentages. However, it is implied that the presented results were deemed acceptable by the FDA.

Key Definitions:

• Essential Agreement (EA): Agreement between the MIC results of the test device and the reference method within plus or minus one doubling dilution.
• Category Agreement (CA): Agreement between the interpretive categories (Susceptible, Intermediate, Resistant) of the test device and the reference method.
• Very Major Error (VME): The test device reports susceptible, but the reference method reports resistant.
• Major Error (ME): The test device reports resistant, but the reference method reports susceptible.
• Minor Error (mE): Any other disagreement in interpretive category (e.g., susceptible vs. intermediate, resistant vs. intermediate).

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

The sample sizes for the test set (external evaluation) are provided for each microorganism:

• C. albicans: 257 isolates
• C. krusei: 76 isolates
• C. parapsilosis: 74 isolates
• C. tropicalis: 87 isolates

Data Provenance: The study conducted an "external evaluation" with "fresh and stock clinical isolates, as well as a set of challenge strains." The document does not specify the country of origin of the data nor explicitly state if it was retrospective or prospective. However, "fresh clinical isolates" typically implies a prospective collection, while "stock clinical isolates" could be either.

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

The ground truth was established by the "CLSI broth microdilution reference method." This is a standardized laboratory method, not reliant on human expert adjudication in the same way an imaging study would be. Therefore, the concept of "experts" and their qualifications as typically applied to visual diagnostic tasks (e.g., radiologists) is not directly applicable here. The ground truth method itself (CLSI broth microdilution) is the expert-defined standard.

4. Adjudication Method for the Test Set:

Not applicable in the human expert sense. The "adjudication method" for determining the ground truth in this context is the CLSI broth microdilution reference method, which serves as the gold standard for antimicrobial susceptibility testing. The device's results are compared directly against this established reference.

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

No, an MRMC comparative effectiveness study was not done. This type of study is relevant for diagnostic devices where human readers interpret results, often in conjunction with AI. The VITEK® 2 AST-Yeast Voriconazole is an automated in vitro diagnostic device for antimicrobial susceptibility testing; its performance is evaluated by comparing its automated output to a gold standard laboratory method, not by how it assists human readers.

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

Yes, a standalone performance evaluation was done. The VITEK® 2 AST-Yeast Voriconazole system is an automated device designed to determine antimicrobial susceptibility without human interpretation of the primary data once the sample is loaded. The performance metrics (Essential Agreement, Category Agreement, error rates) directly reflect the device's standalone capability compared to the reference method.

7. The Type of Ground Truth Used:

The ground truth used was the CLSI broth microdilution reference method, incubated for 24 hours (up to 48 hours for slowly growing isolates). This is a well-established and scientifically accepted standard in microbiology for determining minimum inhibitory concentrations (MICs) of antifungal agents.

8. The Sample Size for the Training Set:

The document does not explicitly state the sample size for the training set. The descriptions focus on the "external evaluation" (test set). For IVD devices like this, the 'training set' often corresponds to historical data, internal studies, and method development efforts that lead to the final algorithm and concentration ranges. Without further information, the exact size of the training set used to develop the VITEK® 2 AST-Yeast Voriconazole algorithm is not provided in this 510(k) summary.

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

Similar to the answer for point 8, the document does not explicitly describe how the ground truth for any potential training set was established. However, given that the final performance is benchmarked against the CLSI broth microdilution reference method, it is highly probable that any internal development or training data would also have used this or a similar established reference method to determine the true susceptibility of isolates.

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VITEK 2 AST-Yeast Anidulafungin is designed for antifungal susceptibility testing of Candida species and is intended for use with the VITEK 2 and VITEK 2 Compact Systems as a laboratory aid in the determination of in vitro susceptibility to antifungal agents. VITEK 2 AST-Yeast Anidulafungin is a quantitative test. Anidulafungin has been shown to be active against most strains of the microorganisms listed below, according to the FDA label for this antifungal.

Active in vitro and in clinical infections: Candida albicans Candida glabrata Candida parapsilosis Candida tropicalis

In vitro data are available, but clinical significance is unknown: Candida guillermondii Candida krusei

The VITEK 2 Fungal Susceptibility Card is intended for use with the VITEK 2 Systems in clinical laboratories as an in vitro test to determine the susceptibility of clinically significant yeasts to antifungal agents when used as instructed.

The principle of the VITEK® 2 AST cards is based on the microdilution minimum inhibitory concentration (MIC) technique reported by MacLowry and Marsh (1) and Gerlach(2). The VITEK® 2 AST card is essentially a miniaturized, abbreviated and automated version of the doubling dilution technique (3).

Each VITEK® 2 AST card contains 64 wells. A control well which only contains microbiological culture media is resident on all cards. The remaining wells contain premeasured portions of a specific antibiotic combined with culture media. The bacterial or yeast isolate to be tested is diluted to a standardized concentration with 0.45 – 0.5% saline before being used to rehydrate the antimicrobial medium within the card. The VITEK® 2 System automatically fills, seals and places the card into the incubator/reader. The VITEK® 2 Compact has a manual filling, sealing and loading operation. The VITEK® 2 Systems monitor the growth of each well in the card over a defined period of time. At the completion of the incubation cycle, a report is generated that contains the MIC value along with the interpretive category result for each antibiotic contained on the card.

VITEK® 2 AST-YS Anidulafungin has the following concentrations in the card: 0.0625, 0.125, 0.5, 2, and 8 (equivalent standard method concentration by efficacy in ug/mL).

Here's an analysis of the acceptance criteria and the study proving the device meets those criteria, based on the provided text.

Device: VITEK 2 AST-Yeast Anidulafungin

Indications for Use: Antifungal susceptibility testing of Candida species (C. albicans, C. glabrata, C. parapsilosis, C. tropicalis, C. guilliermondii, C. krusei) as a laboratory aid in determining in vitro susceptibility to antifungal agents.

1. Table of Acceptance Criteria and Reported Device Performance

The provided document doesn't explicitly state the acceptance criteria in a separate table directly defining thresholds for Essential Agreement (EA), Category Agreement (CA), or error rates (VME, ME, mE) that the device must meet for approval. Instead, it presents the results of the performance study and implies that these results were deemed "acceptable" by the FDA. The performance is compared to the "CLSI broth microdilution reference method, as defined in the FDA Class II Special Controls Guidance Document: Antimicrobial Susceptibility Test (AST) Systems; Guidance for Industry and FDA (Issued August 28, 2009)". This guidance document would contain the specific acceptance criteria.

However, based on the presented "Performance Overview" (Page 7) and the overall context of AST device approvals, typical acceptance criteria for Essential Agreement and Category Agreement are usually in the range of 90-95% or higher, with Very Major Error (VME) and Major Error (ME) rates usually being low (e.g.,

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The VIDAS® TBI (GFAP, UCH-L1) test is composed of two automated assays - VIDAS® TBI (GFAP) and VIDAS® TBI (UCH-L1) - to be used on the VIDAS® 3 instrument for the quantitative measurement of Glial Fibrillary Acidic Protein (GFAP) and Ubiquitin C-terminal Hydrolase (UCH-L1) in human serum using the ELFA (Enzyme Linked Fluorescent Assay) technique. The results of both assays are requred to obtain an overall qualitative test interpretation.

The overall qualitative VIDAS® TBI (GFAP, UCH-L1) test result is used, in conjunction with clinical information, to aid in the evaluation of patients (18 years of age or older), presenting within 12 hours of suspected mild traumatic brain injury (Glasgow Coma Scale score 13-15), to assist in determining the need for a Computed Tomography (CT) scan of the head. A negative interpretation of VIDAS® TBI (GFAP, UCH-L1) test is associated with the absence of acute intracranial lesions visualized on a head CT scan.

The VIDAS® TBI (GFAP, UCH-L1) test is composed of two automated assays – VIDAS® TBI (GFAP) and VIDAS® TBI (UCH-L1) – to be used on the VIDAS® 3 instrument. Similar to other VIDAS assays, VIDAS TBI (GFAP) and VIDAS TBI (UCH-L1) test kits (specific to each biomarker) contain the solid phase receptacles (SPRs®), the reagent strips, Product Calibrator S1 and Product Control C1. These test kits will also contain the master lot entry (MLE) data i.e., a barcode printed on the outer label of the packaging, as well as the reference number of the package insert to download from the bioMérieux website.

Whether it be for the GFAP or UCH-L1 quantification, the test combines a three-step enzyme immunoassay sandwich method with a final fluorescent detection step, also known as enzyme-linked fluorescent assay (ELFA).

The Solid Phase Receptacle (SPR) serves as the solid phase as well as the pipetting device. The inner surface of the SPR is coated with antibodies aqainst the substance of interest i.e., anti-GFAP or anti-UCH-L1 antibodies. The reagent strip consists of 10 wells covered with a labeled foil seal. Well 1 is designated for the sample. Eight of the wells contain sample diluent, wash buffer, conjugate, and tracer. The last well contains the fluorescent substrate. All of the assay steps are performed automatically by the instrument.

The intensity of the fluorescence is proportional to the concentration of the analyte the sample. At the end of the assay, the biomarker concentration is automatically calculated by the instrument in relation to the calibration curve and stored in the Master Lot Entry (MLE) data.

VIDAS TBI (GFAP) and VIDAS TBI (UCH-L1) results are reported separately: the VIDAS 3 reports the calculated concentration and the qualitative interpretation for each. The final result i.e., the patient's status in relation to suspected mild traumatic brain injury, must be interpreted by the user according to the decision tree presented in the package insert.

This document describes the validation of the VIDAS® TBI (GFAP, UCH-L1) test, an automated assay for diagnosing mild traumatic brain injury. The submission compares the device to a predicate device, the BANYAN BTI™, and summarizes non-clinical and clinical testing results. The following points address the requested information based on the provided text:

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

The document does not explicitly state "acceptance criteria" for each performance metric in a table format. However, it presents the results of various assays and often implies that the results "demonstrate" or "confirm" the required performance, indicating these are the achieved results compared to an internal standard or regulatory expectation. Below is a table summarizing various performance metrics and their reported results. Specific acceptance criteria values are not provided in this public summary.

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

• Test set sample size: For the diagnostic accuracy study, the sample size is not explicitly stated but refers to the "ALERT cohort." For the reference interval study, 513 apparently healthy US adult subjects were used.
• Data provenance: The diagnostic accuracy study was performed using the "ALERT cohort." The reference interval study was conducted at three sites (one internal European site and two external US sites). It is not specified whether these studies were retrospective or prospective, though "ALERT cohort" could suggest a pre-existing dataset.

3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts (e.g., radiologist with 10 years of experience)

This information is not provided in the document. The diagnostic accuracy study compares the device's results to the presence/absence of acute intracranial lesions visualized on a head CT scan, but the number or qualifications of experts interpreting these CT scans to establish ground truth are not mentioned.

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

This information is not provided in the 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

A multi-reader multi-case (MRMC) comparative effectiveness study was not performed. This device is an in vitro diagnostic test for quantitative measurement of biomarkers, not an AI-assisted imaging device that impacts human reader performance.

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

Yes, the diagnostic accuracy study presents the standalone performance of the VIDAS® TBI (GFAP, UCH-L1) assay. The results (sensitivity, specificity, etc.) are based on the device's output compared to the ground truth (CT scan findings). The device is used "in conjunction with clinical information," but the reported diagnostic accuracy figures are for the test itself.

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

The ground truth for the diagnostic accuracy study was "absence of acute intracranial lesions visualized on a head CT scan." This indicates that CT scan results were used as the reference standard for traumatic brain injury assessment.

8. The sample size for the training set

This document describes a diagnostic device and its validation. It does not explicitly mention a "training set" in the context of machine learning or AI models with distinct training and test phases. The "test set" for diagnostic accuracy is referred to as the "ALERT cohort." The reference interval was established using 513 apparently healthy subjects.

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

As there is no explicitly defined "training set" for an AI model in this submission, the method for establishing ground truth for a training set is not applicable or described. The clinical performance data presented (Diagnostic Accuracy and Reference interval) seems to represent the evaluation of the final device.

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VITEK® 2 AST-Gram Positive Lefamulin is designed for antimicrobial susceptibility testing of Gram positive microorganisms and is intended for use with the VITEK® 2 and VITEK® 2 Compact Systems as a laboratory aid in the determination of in vitro susceptibility to antimicrobial agents.

VITEK® 2 AST-Gram Positive Lefamulin is a quantitative test. Lefamulin has been shown to be active against most strains of the microorganisms listed below, according to the FDA label for this antimicrobial.

Active both in vitro and in clinical infections: Staphylococcus aureus (methicillin-susceptible isolates)

The VITEK® 2 Gram-positive Susceptibility Card is intended for use with the VITEK® 2 Systems in clinical laboratories as an in vitro test to determine the susceptibility of Staphylococcus spp., and S. agalactive to antimicrobial agents when used as instructed.

The principle of the VITEK® 2 AST cards is based on the microdilution minimum inhibitory concentration (MIC) technique reported by MacLowry and Marsh (1) and Gerlach (2). The VITEK® 2 AST card is essentially a miniaturized, abbreviated and automated version of the doubling dilution technique (0).

Each VITEK® 2 AST card contains 64 wells. A control well which only contains microbiological culture media is resident on all cards. The remaining wells contain premeasured portions of a specific antibiotic combined with culture media. The bacterial or yeast isolate to be tested is diluted to a standardized concentration with 0.45 - 0.5% saline before being used to rehydrate the antimicrobial medium within the card. The VITEK® 2 System automatically fills, seals and places the card into the incubator/reader. The VITEK® 2 Compact has a manual filling, sealing and loading operation. The VITEK® 2 Systems monitor the growth of each well in the card over a defined period of time. At the completion of the incubation cycle, a report is generated that contains the MIC value along with the interpretive category result for each antibiotic contained on the card.

VITEK® 2 AST-GP Lefamulin (≤ 0.03 –>4 µg/mL) has the following concentrations in the card: 0.125, 0.5, 1, and 2 (equivalent standard method concentration by efficacy in ug/mL).

The VITEK® 2 AST-Gram Positive Lefamulin (≤ 0.03 - ≥4 µg/mL) device is an antimicrobial susceptibility testing system designed for Gram-positive microorganisms. The acceptance criteria and performance of the device are detailed below.

1. Table of Acceptance Criteria and Reported Device Performance

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

The test set included:

• 404 isolates for Essential Agreement reporting and 404 isolates for Category Agreement reporting (derived from the numerators/denominators in Table 2).
• 3 resistant isolates were tested for VME (Very Major Error)
• 401 susceptible isolates were tested for ME (Major Error)

The data provenance is described as an "external evaluation" conducted with "fresh and stock clinical isolates, as well as a set of challenge strains." The document does not specify the country of origin of the data or explicitly state whether the study was retrospective or prospective.

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

This information is not provided in the given text.

4. Adjudication method for the test set

This information is not provided in the given text.

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

A multi-reader multi-case (MRMC) comparative effectiveness study with human readers assisted by AI is not applicable to this device. This device is an automated antimicrobial susceptibility test system, not an AI-assisted diagnostic tool interpreted by human readers.

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

Yes, a standalone performance evaluation was done. The VITEK® 2 AST-GP Lefamulin system's performance was compared directly to the CLSI broth microdilution reference method (the ground truth), without human intervention in the interpretation of the VITEK® 2 results. The system automatically generates MIC values and interpretive categories.

7. The type of ground truth used

The ground truth used was the CLSI broth microdilution reference method, incubated at 16-20 hours.

8. The sample size for the training set

The document does not explicitly mention a separate "training set" or its sample size. The description focuses on the external evaluation data used for performance assessment. As an AST system, the device's "training" for MIC determination is inherent in its design based on established microdilution principles and may not involve a distinct, large-scale machine learning training set in the way an AI algorithm might.

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

Since a distinct training set is not explicitly mentioned as per the prompt's context (e.g., for an AI algorithm), details on how its ground truth was established are not provided. The device's operation is based on established microbiological principles, and its performance is validated against the CLSI broth microdilution reference method.

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VITEK® 2 Streptococcus Penicillin is designed for antimicrobial susceptibility testing of Streptococcus species and is intended for use with the VITEK® 2 and VITEK® 2 Compact Systems as a laboratory aid in the determination of in vitro susceptibility to antimicrobial agents. VITEK® 2 Streptococcus Penicillin is a quantitative test. Penicillin has been shown to be active against most strains of the microorganisms listed below, according to the FDA label for this antimicrobial.

Active both in vitro and in clinical infections: Beta hemolytic Streptococci groups C and G Streptococcus pyogenes Streptococcus agalactiae Streptococcus viridans group Streptococcus pneumoniae

The VITEK® 2 Streptococcus Susceptibility Card is intended for use with the VITEK® 2 Systems in clinical laboratories as an in vitro test to determine the susceptibility of Sireptococcus pneumoniae, beta-hemolytic Streptococcus, and Viridans Streptococcus to antimicrobial agents when used as instructed.

The principle of the VITEK® 2 AST cards is based on the microdilution minimum inhibitory concentration (MIC) technique reported by MacLowry and Marsh(1) and Gerlach(2). The VITEK® 2 AST card is essentially a miniaturized, abbreviated and automated version of the doubling dilution technique(3).

Each VITEK® 2 AST card contains 64 wells. A control well which only contains microbiological culture media is resident on all cards. The remaining wells contain premeasured portions of a specific antibiotic combined with culture media. The bacterial or yeast isolate to be tested is diluted to a standardized concentration with 0.45 - 0.5% saline before being used to rehydrate the antimicrobial medium within the card. The VITEK® 2 System automatically fills, seals and places the card into the incubator/reader. The VITEK® 2 Compact has a manual filling, sealing and loading operation. The VITEK® 2 Systems monitor the growth of each well in the card over a defined period of time. At the completion of the incubation cycle, a report is generated that contains the MIC value along with the interpretive category result for each antibiotic contained on the card.

VITEK® 2 Streptococcus Penicillin has the following concentrations in the card: 0.06, 0.12, 0.5, and 2ug/mL (equivalent standard method concentration by efficacy in ug/mL).

Here's a summary of the acceptance criteria and study details for the VITEK® 2 Streptococcus Penicillin device:

1. Acceptance Criteria and Reported Device Performance

The device performance is compared to the broth microdilution reference method. The key metrics are Essential Agreement (EA) and Category Agreement (CA), along with Very Major Errors (VME), Major Errors (ME), and Minor Errors (mE).

The document states that the device "demonstrated substantially equivalent performance when compared with the broth microdilution reference method, as defined in the FDA Class II Special Controls Guidance Document: Antimicrobial Susceptibility Test (AST) Systems; Guidance for Industry and FDA (Issued August 28, 2009)." This guidance document typically outlines specific numerical acceptance criteria for EA, CA, VME, ME, and mE, which are implicitly met by the reported percentages being considered "acceptable."

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

The sample sizes for the test set are embedded within the "Reported Device Performance" column (e.g., 350 for Streptococcus pneumoniae (non-meningitis), 391 for Streptococcus Viridans group, 833 for Beta-hemolytic Streptococcus).

The data provenance is from "external evaluation... conducted with fresh and stock clinical isolates, as well as a set of challenge strains." This implies a combination of retrospective (stock clinical isolates) and prospective (fresh clinical isolates) data. The country of origin of the data is not specified in the provided text.

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

This information is not provided in the document. The ground truth is established by the CLSI broth microdilution reference method, but details on expert involvement in this process (e.g., reading/interpreting the reference method results) are not mentioned.

4. Adjudication Method for the Test Set

This information is not explicitly provided in the document. The study compares the VITEK® 2 results to the CLSI broth microdilution reference method. Adjudication might be part of the standard CLSI method, but it is not detailed here for discrepancies.

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

No, a multi-reader multi-case (MRMC) comparative effectiveness study was not done. This study focuses on the performance of an automated diagnostic device against a reference method, not on 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 study was done. The VITEK® 2 system is a "Fully Automated Short-Term Incubation Cycle Antimicrobial Susceptibility System," and its performance was evaluated against the CLSI broth microdilution reference method. This is an evaluation of the algorithm's output (MIC values and interpretive categories) without direct human intervention in the interpretation of the VITEK® 2 results.

7. The Type of Ground Truth Used

The type of ground truth used is the broth microdilution reference method, specifically the CLSI method incubated at 16-20 hours. This is typically considered the gold standard for antimicrobial susceptibility testing.

8. The Sample Size for the Training Set

The document does not explicitly state the sample size for the training set. The study describes "external evaluation" for performance, but it doesn't separate out a specific training set size for the VITEK® 2 algorithm itself.

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

The document does not explicitly state how the ground truth for any training set was established, as it primarily focuses on the performance evaluation of the final device against a reference method. However, given that the device is an "Automated quantitative antimicrobial susceptibility test," it's highly probable that any internal training/development would have used an established reference method (like broth microdilution) to establish ground truth for algorithm development.

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VITEK® 2 AST-Gram Positive Daptomycin is designed for antimicrobial susceptibility testing of Gram positive microorganisms and is intended for use with the VITEK® 2 Compact Systems as a laboratory aid in the determination of in vitro susceptibility to antimicrobial agents. VITEK® 2 AST-Gram Positive Daptomycin is a quantitative test. Daptomycin has been shown to be active against most strains of the microorganisms listed below, according to the FDA label for this antimicrobial.

Active both in vitro and in clinical infections: Enterococcus faecalis (vancomycin-susceptible isolates only) Staphylococcus aureus (including methicillin-resistant isolates)

In vitro data are available, but their clinical significance is unknown: Enterococcus faecalis (vancomycin-resistant isolates)

The VITEK® 2 Gram-positive Susceptibility Card is intended for use with the VITEK® 2 Systems in clinical laboratories as an in vitro test to determine the susceptibility of Staphylococcus spp., Enterococcus spp., and S. agalactiae to antimicrobial agents when used as instructed.

The principle of the VITEK® 2 AST cards is based on the microdilution minimum inhibitory concentration (MIC) technique reported by MacLowry and Marsh(1) and Gerlach(2). The VITEK® 2 AST card is essentially a miniaturized, abbreviated and automated version of the doubling dilution technique(3).

Each VITEK® 2 AST card contains 64 wells. A control well which only contains microbiological culture media is resident on all cards. The remaining wells contain premeasured portions of a specific antibiotic combined with culture media. The bacterial or yeast isolate to be tested is diluted to a standardized concentration with 0.45 - 0.5% saline before being used to rehydrate the antimicrobial medium within the card. The VITEK® 2 System automatically fills, seals and places the card into the incubator/reader. The VITEK® 2 Compact has a manual filling, sealing and loading operation. The VITEK® 2 Systems monitor the growth of each well in the card over a defined period of time. At the completion of the incubation cycle, a report is generated that contains the MIC value along with the interpretive category result for each antibiotic contained on the card.

VITEK® 2 AST-GP Daptomycin has the following concentrations in the card: 0.5, 1, 2, 4, and 8 ug/mL (equivalent standard method concentration by efficacy in ug/mL).

The provided document describes the VITEK® 2 AST-GP Daptomycin system, an antimicrobial susceptibility test, and its performance evaluation.

Here's an analysis of the acceptance criteria and the study proving the device meets them:

1. Table of Acceptance Criteria and Reported Device Performance

The acceptance criteria for antimicrobial susceptibility test (AST) systems in the US are generally defined by the FDA Class II Special Controls Guidance Document: Antimicrobial Susceptibility Test (AST) Systems. While specific numerical targets for Essential Agreement (EA) and Category Agreement (CA) are usually outlined in this guidance, the summary states the device demonstrated substantially equivalent performance when compared with the broth microdilution reference method, as defined in the FDA Class II Special Controls Guidance Document.

The reported performance of the VITEK® 2 AST-GP Daptomycin is provided in "Table 2: VITEK® 2 AST-GP Daptomycin Performance".

Note on VME/ME/mE for Staphylococcus aureus: The document lists "N/A" for VME and mE for Staphylococcus aureus and "0.0%" for ME for Enterococcus faecalis. This might indicate that no specific VME/ME/mE were observed or reported in those categories, or that the formatting of the table in the document itself uses N/A for cases where a specific error type threshold wasn't relevant or wasn't met to be explicitly calculated. However, for a complete picture, the FDA guidance document would provide the specific acceptance thresholds for these error types. The (1/8) 12.5% VME for Enterococcus faecalis and (41/270) 15.2% mE for Enterococcus faecalis would likely be subject to specific acceptance criteria limits in the FDA guidance; for example, VMEs are typically expected to be ≤ 1.5% and MEs ≤ 3.0%, while mEs generally have a higher tolerance but still a limit. The document states a 90.5% overall Category Agreement, which for Enterococcus faecalis alone is 84.4%, falling below the typical 90% threshold for CA. This discrepancy might be addressed in a larger context within the full premarket notification, or perhaps the overall performance across all tested species met the required threshold despite one species being lower.

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

• Test Set Sample Size:
  • Staphylococcus aureus: 194 isolates
  • Enterococcus faecalis: 270 isolates
  • Total Clinical Isolates in Performance Study: 194 + 270 = 464 isolates.
  • The study also used a "set of challenge strains" in addition to fresh and stock clinical isolates, but the exact number of challenge strains is not specified in this summary.
• Data Provenance:
  • "An external evaluation was conducted with fresh and stock clinical isolates, as well as a set of challenge strains." This suggests a prospective or a mix of prospective and retrospective collection from external sources (likely clinical laboratories).
  • The document does not specify the country of origin for the data.

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

• The ground truth was established by the CLSI broth microdilution reference method. This method is a standardized laboratory procedure, not reliant on human expert interpretation in the same way as, for example, image reading. Therefore, "number of experts" and "qualifications of experts" are not directly applicable in the context of establishing ground truth for this type of antimicrobial susceptibility testing.

4. Adjudication Method for the Test Set

• The reference method itself (CLSI broth microdilution) serves as the "ground truth" or "adjudication." No separate human adjudication process (e.g., 2+1, 3+1 consensus) is applicable or mentioned for this type of in vitro diagnostic device study. The device's results are directly compared to the results of the reference method.

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 type of study design is typically used for AI-powered diagnostic imaging devices where human readers interpret images with or without AI assistance. This device is an automated in vitro diagnostic system for antimicrobial susceptibility testing, not requiring human interpretation of complex visual data for its primary function.

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

• Yes, the performance study effectively evaluates the "standalone" performance of the VITEK® 2 AST-GP Daptomycin system. The system automatically processes the samples and generates MIC values and interpretive categories, which are then compared directly to the CLSI broth microdilution reference method. There is no human intervention in the device's determination of susceptibility.

7. The Type of Ground Truth Used

• The ground truth used was the CLSI broth microdilution reference method, which is a highly standardized and accepted laboratory method for determining antimicrobial susceptibility. This is essentially a "gold standard" laboratory method.

8. The Sample Size for the Training Set

• The document does not provide information on the training set size. This type of premarket notification summary focuses on the performance evaluation of the final device, not typically on the specific dataset used for algorithm development or training. The "Discriminant Analysis" mentioned under "Analysis Algorithms" implies a statistical model was used, which would have been developed/trained on a dataset, but details of this dataset are not included in this summary.

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

• As the training set details are not provided, the method for establishing its ground truth is also not described in this summary. It would logically be established using a similar or identical reference method to the test set, but this is not confirmed.

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VITEK® 2 AST-Gram Negative Levolloxacin is designed for antimicrobial susceptibility testing of Gram-negative bacilli and is intended for use with the VITEK® 2 and VITEK® 2 Compact Systems as a laboratory aid in the determination of in vito susceptibility to antimicrobial agents. VITEK® 2 AST-Gram Negative Levofloxacin is a quantitative test. Levolloxacin has been shown to be active against most strains of the microorganisms listed below, according to the FDA label for this antimicrobial.

Active in vitro and in clinical infections: Enterchacter cloacae, Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Pseudomonas aeruginosa, Serratia marcescens

Active in vitro but clinical significance unknown: Citrobacter freundii, Enterobacter aerogenes, Klebsiella oxytoca, Morganii, Pantoea agglomerans, Proteus vulgaris, Providencia rettgeri, Providencia stuartii

VITEK® 2 AST-Gram Negative Levofloxacin also reports the susceptibility for the following additional organism as listed on the FDA Susceptibility Test Interpretive Criteria website: Salmonella spp.

The VITEK® 2 Gram-Negative Susceptibility Card is intended for use with the VITEK® 2 Systems in clinical laboratories as an in vitro test to determine the susceptibility of clinically significant aerobic Gram-negative bacilli to antimicrobial agents when used as instructed.

The principle of the VITEK® 2 AST cards is based on the microdilution minimum inhibitory concentration (MIC) technique reported by MacLowry and Marsh (1) and Gerlach (2). The VITEK® 2 AST card is essentially a miniaturized, abbreviated and automated version of the doubling dilution technique (3).

Each VITEK® 2 AST card contains 64 wells. A control well which only contains microbiological culture media is resident on all cards. The remaining wells contain premeasured portions of a specific antibiotic combined with culture media. The bacterial or yeast isolate to be tested is diluted to a standardized concentration with 0.45 - 0.5% saline before being used to rehydrate the antimicrobial medium within the card. The VITEK® 2 System automatically fills, seals and places the card into the incubator/reader. The VITEK® 2 Compact has a manual filling, sealing and loading operation. The VITEK® 2 Systems monitor the growth of each well in the card over a defined period of time. At the completion of the incubation cycle, a report is generated that contains the MIC value along with the interpretive category result for each antibiotic contained on the card.

VITEK® 2 AST-GN Levofloxacin has the following concentrations in the card: 0.25, 0.5, 2, and 8 (equivalent standard method concentration by efficacy in ug/mL).

Here's a breakdown of the acceptance criteria and the study details for the VITEK® 2 AST-Gram Negative Levofloxacin device, based on the provided FDA 510(k) summary:

1. Acceptance Criteria and Reported Device Performance

The acceptance criteria are implicitly defined by the FDA Class II Special Controls Guidance Document for Antimicrobial Susceptibility Test (AST) Systems. The performance metrics reported are Essential Agreement (EA), Category Agreement (CA), Very Major Errors (VME), Major Errors (ME), and minor Errors (mE). Reproducibility and Quality Control also demonstrated acceptable results, although specific percentage thresholds for these are not provided in this summary.

Here's the table of reported device performance:

Notes on Interpretation from the document:

• VITEK 2 Levofloxacin MIC values for Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa tended to be in exact agreement or at least one doubling dilution higher when compared to the reference agar dilution method.
• VITEK 2 Levofloxacin MIC values for Serratia marcescens tended to be in exact agreement or at least one doubling dilution lower when compared to the reference agar dilution method.

2. Sample Size and Data Provenance

The sample sizes for the test set are embedded within the performance data (e.g., 346 for Enterobacterales, 225 for Pseudomonas aeruginosa, 48 for Salmonella spp.). These numbers represent the total number of isolates tested for each organism group.

The data provenance is described as an "external evaluation" conducted with "fresh and stock clinical isolates, as well as a set of challenge strains." The document does not specify the country of origin, but "external" implies outside of the manufacturer's immediate control. The use of "fresh and stock clinical isolates" indicates a mix of prospective (fresh) and retrospective (stock) data, augmented by specific challenge strains.

3. Number of Experts and Qualifications for Ground Truth

The document does not explicitly state the number of experts used or their specific qualifications (e.g., "radiologist with 10 years of experience"). However, the ground truth is established by the "CLSI agar dilution reference method incubated between 16-20 hours." This method is a standardized laboratory procedure, and implicitly requires trained laboratory professionals to perform and interpret, but it's not based on expert consensus in the typical sense of diagnostic imaging or clinical interpretation.

4. Adjudication Method

The concept of "adjudication" in the sense of multiple experts reviewing and reaching a consensus on a case (like 2+1 or 3+1) is not applicable here. The ground truth is determined by a single, standardized reference laboratory method (CLSI agar dilution). Any discrepancies would be between the VITEK 2 device's result and this reference method, leading to the error rates (VME, ME, mE) reported.

5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study

No, a Multi-Reader Multi-Case (MRMC) comparative effectiveness study was not conducted as described. This type of study typically involves human readers or clinicians making diagnoses with and without AI assistance to measure improvement in human performance. The VITEK 2 device is a fully automated laboratory device, and the study compares its performance directly against a reference laboratory method, not against human interpretation of the images/data it produces.

6. Standalone Performance Study

Yes, a standalone (algorithm only without human-in-the-loop performance) study was done. The entire performance evaluation reported in the 510(k) summary is of the VITEK 2 device's output (MIC values and interpretive categories) compared directly to the CLSI agar dilution reference method. The device is intended to be automated, and its performance is assessed independently.

7. Type of Ground Truth Used

The ground truth used is the CLSI agar dilution reference method results. This is a recognized standard laboratory method for determining antimicrobial susceptibility, considered the gold standard for this type of in vitro diagnostic test. It is not based on expert consensus, pathology, or outcomes data in the usual clinical sense, but rather a robust, objective laboratory measurement.

8. Sample Size for the Training Set

The document does not specify the sample size for the training set. It describes the data used for the "external evaluation" (test set) but provides no information about the isolates used to develop or train the VITEK® 2 AST-GN Levofloxacin system's algorithms (Discriminant Analysis).

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

The document does not provide details on how the ground truth for the training set was established. However, given the nature of AST systems, it is highly probable that the training set's ground truth would have also been established using a similar, if not identical, reference method like the CLSI agar dilution method. The device's "Discriminant Analysis" algorithms would have been developed and optimized to correlate its readings with these reference standard results.

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VITEK® 2 AST-Gram Negative Plazomicin is designed for antimicrobial susceptibility testing of Gram negative bacilli and is intended for use with the VITEK® 2 and VITEK® 2 Compact Systems as a laboratory aid in the determination of in vitro susceptibility to antimicrobial agents. VITEK® 2 AST-Gram Negative Plazomicin is a quantitative test. Plazomicin has been shown to be active against most strains of the microorganisms listed below, according to the FDA label for this antimicrobial.

Active both in vitro and in clinical infections: Escherichia coli Klebsiella pneumoniae Enterobacter cloacae

In vitro data are available, but their clinical significance is unknown:

Citrobacter freundii Citrobacter koseri Klebsiella (Enterobacter) aerogenes Klebsiella oxytoca Proteus vulgaris Serratia marcescens

The VITEK® 2 Gram-Negative Susceptibility Card is intended for use with the VITEK® 2 Systems in clinical laboratories as an in vitro test to determine the susceptibility of clinicaly significant aerobic bacilli to antimicrobial agents when used as instructed.

The principle of the VITEK® 2 AST cards is based on the microdilution minimum inhibitory concentration (MIC) technique reported by MacLowry and Marsh(4) and Gerlach(2). The VITEK® 2 AST card is essentially a miniaturized, abbreviated and automated version of the doubling dilution technique(3).

Each VITEK® 2 AST card contains 64 wells. A control well which only contains microbiological culture media is resident on all cards. The remaining wells contain premeasured portions of a specific antibiotic combined with culture media. The isolate to be tested is diluted to a standardized concentration with 0.45 - 0.5% saline before being used to rehydrate the antimicrobial medium within the card. The VITEK® 2 System automatically fills, seals and places the card into the incubator/reader. The VITEK® 2 Compact has a manual filling, sealing and loading operation. The VITEK® 2 Systems monitor the growth of each well in the card over a defined period of time. At the completion of the incubation cycle, a report is generated that contains the MIC value along with the interpretive category result for each antibiotic contained on the card.

This document, K223478, describes the premarket notification for the VITEK® 2 AST-GN Plazomicin antimicrobial susceptibility testing system. The device is intended to determine the in vitro susceptibility of Gram-negative bacilli to Plazomicin.

Here's an analysis of the acceptance criteria and the study proving the device meets them:

1. Table of Acceptance Criteria and Reported Device Performance

The acceptance criteria for antimicrobial susceptibility testing (AST) devices are typically based on Essential Agreement (EA) and Category Agreement (CA), along with limits for Very Major Errors (VME), Major Errors (ME), and Minor Errors (mE), as defined by the FDA Class II Special Controls Guidance Document: Antimicrobial Susceptibility Test (AST) Systems. While the document doesn't explicitly state numerical acceptance criteria for each error type (e.g., "VME must be

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