Search Results

The Invader® Factor V test is an in vitro diagnostic test intended for the detection and genotyping of a single point mutation (G to A at position 1691) of the human Factor V gene in isolated genomic DNA obtained from whole blood potassium EDTA samples from patients with suspected thrombophilia.

The Invader Factor V test consists of the following components: Factor V Oligo Mix, Universal Buffer, Universal Enzyme Mix, No DNA Control, Factor V Wild Type Control, Factor V Heterozygous Control, Factor V Mutant Control, Invader Call Reporter™ Software, Invader® Factor V Software.

Here's an analysis of the acceptance criteria and supporting study details for the Invader® Factor V test, based on the provided text:

Acceptance Criteria and Device Performance for Invader® Factor V Test

1. Table of Acceptance Criteria and Reported Device Performance

The submission primarily focuses on analytical performance criteria, demonstrating the assay's reliability and accuracy in detecting the Factor V G1691A mutation.

2. Sample Size for Test Set and Data Provenance

• External Reproducibility (Study #1):
  • Sample Size: 9 unique leukocyte-depleted whole blood samples (3 wild type, 3 heterozygous, 3 homozygous mutant) spiked cell lines.
  • Provenance: "Spiked cell lines" implies controlled, laboratory-prepared samples. The text does not specify the country of origin, but the study was conducted at "3 different sites (2 external sites and 1 internal site)", suggesting multi-center testing, likely within the US given the FDA submission. This was a prospective study where samples were tested newly.
• Lot-to-Lot Reproducibility (Study #9):
  • Sample Size: 5 genomic DNA samples (3 wild type, 2 heterozygous).
  • Provenance: Not explicitly stated, likely laboratory-prepared or acquired genomic DNA.
• Real-Time Stability (Study #5):
  • Sample Size: Samples representing all three genotypes (WT, HET, MUT) (number not explicitly stated, but tested in quadruplicate at each time point). Also mentions three product lots.
  • Provenance: Likely laboratory-prepared/controlled samples.
• Reagent Freeze-Thaw Stability (Study #6):
  • Sample Size: Controls (WT, HET, MUT) and gDNA (WT, HET, MUT). Total of 255 tests.
  • Provenance: Genomic DNA isolate from cell lines.
• Detection limit/Analytical Sensitivity and Normal Range (Study #3):
  • Sample Size: 2 genomic DNA samples (1 WT, 1 HET), each diluted to 8 concentrations and tested in 40 replicates (total 2 * 8 * 40 = 640 tests).
  • Provenance: Genomic DNA extracted from whole blood collected in potassium EDTA.
• Analytical specificity (Study #4):
  • Sample Size: 4 whole blood samples (3 WT, 1 HET). Each substance tested on 8 of these samples.
  • Provenance: Human whole blood samples.
• Pre-Analytical Equivalency Study (Study #7):
  • Sample Size: 30 human whole blood samples and 10 leukocyte-depleted whole blood spike cell lines (total 40 unique samples). These were processed by 4 different extraction methods, leading to 160 extracted DNAs.
  • Provenance: Human whole blood samples and cell lines.
• Instrument Equivalency (Study #8):
  • Sample Size: 29 human whole blood samples and 10 leukocyte-depleted whole blood samples spiked with cell lines (total 39 unique samples). These were tested across various instrument combinations, leading to 78 samples per combination (likely some samples were tested multiple times or a subset of the 39 samples were used to create 78 data points.
  • Provenance: Human whole blood samples and cell lines.
• Secondary Polymorphism Impact (Study #10):
  • Sample Size: 5 samples (one homozygous normal, one heterozygous, and three homozygous normal with different secondary polymorphisms). Tested in 40 replicates each (total 5 * 40 = 200 tests).
  • Provenance: Known Factor V genotypes with or without secondary polymorphisms.
• Method comparison (Bi-directional Sequencing) (Study #2):
  • Sample Size: 352 human whole blood samples (289 Homozygous Wild Type (GG), 45 Heterozygous (GA), 18 Homozygous Mutant (AA)).
  • Provenance: Human whole blood samples. The text does not specify the country of origin, but it is implied to be a retrospective collection based on the phrasing "underwent DNA extraction and subsequent bi-directional DNA sequence analysis" then "The same DNA samples were then analyzed using the Invader® Factor V test."

3. Number of Experts and Qualifications for Ground Truth

The primary method for establishing ground truth across most studies is bi-directional DNA sequencing. The text does not specify the number of experts or their specific qualifications (e.g., molecular geneticists) used to interpret these sequencing results. However, bi-directional sequencing is a standard and highly accurate method for genotyping, and its interpretation would typically be performed by trained molecular diagnosticians or geneticists.

4. Adjudication Method for the Test Set

The text does not explicitly describe an adjudication method (e.g., 2+1, 3+1). For discrepancies, the sequencing results are considered the gold standard to which the device's results are compared. In cases like the "No Call" results in Study #1, troubleshooting and retraining of the operator were performed, and retesting was done against sequencing as the reference.

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

No, an MRMC comparative effectiveness study involving human readers with and without AI assistance was not done.

This device (Invader® Factor V test) is an in vitro diagnostic assay for genotyping, not an AI-assisted diagnostic imaging or clinical decision support system that would typically involve human readers. Its output is a genotype call (WT, HET, MUT), which is then interpreted by a healthcare professional. Therefore, the concept of "how much human readers improve with AI vs without AI assistance" does not apply to this type of device.

6. Standalone (Algorithm Only) Performance

Yes, the standalone performance (algorithm only without human-in-the-loop performance) was done and is the primary focus of the performance studies.

The Invader® Factor V test is an automated in vitro diagnostic system. The "Invader® Factor V Software, in combination with Invader Call Reporter™ software," processes raw fluorescence data to determine genotype calls (WT, HET, MUT). All the performance studies described (Precision, Stability, Sensitivity, Specificity, Method Comparison, etc.) evaluate the accuracy of these software-generated genotype calls against a recognized gold standard (bi-directional sequencing). There is no "human-in-the-loop" step described for data interpretation that would alter the genotype call generated by the software. The human operator's role is primarily experimental execution and loading/reviewing results from the software.

7. Type of Ground Truth Used

The primary type of ground truth used across all studies is bi-directional DNA sequencing. Where applicable, expected genotypes from known control materials (cell lines) also served as ground truth. This is a highly accurate and widely accepted method for determining genetic mutations.

8. Sample Size for the Training Set

The document does not explicitly mention a separate "training set" for the device's algorithm. For in vitro diagnostic kits like the Invader® Factor V test, the "training" (development and optimization) phase would typically involve a proprietary set of samples used by the manufacturer to establish the assay parameters, cutoff values for fluorescence, and the logic within the software for genotype calling. These samples are not typically disclosed or enumerated as a formal "training set" in regulatory submissions but are part of the overall development process. The studies described are validation studies (test sets) demonstrating the finalized device's performance.

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

Since a formal "training set" is not explicitly defined in the provided document, the method for establishing ground truth for any internal development samples would likely be the same as for the validation studies: bi-directional DNA sequencing, or comparison to previously characterized genomic DNA samples.

Ask a specific question about this device

The VeraCode Genotyping Test for Factor V and Factor II is an in vitro diagnostic device for the detection and genotyping of Factor V Leiden G1691A and Factor II (Prothrombin) G20210A point mutations in DNA obtained from EDTA-anticoagulated human blood samples. The test is intended for use on the BeadXpress System. The VeraCode Genotyping Test for Factor V and Factor II on the BeadXpress System is indicated for use as an aid to diagnosis in the evaluation of patients with suspected thrombophilia.

The VeraCode Genotyping Test for Factor V and Factor II assay consists of reagents sufficient for 96 tests, consisting of two boxes containing pre-PCR and post-PCR reagents. The pre-PCR box contains the following reagents: MTR1 (1 x 1.2 mL). AB1 (1 x 4 mL), AOP1 (1 x 4.8 mL), ELM (1 x 4.8 mL), FSB (1 x 4.8mL), UB3 buffer (2 x 4.8 mL) and AE1 reagent (2 x 4.8 mL). The post-PCR box contains MSS reagent (1 x 4.8 mL) and Fast Start Taq DNA Polymerase (1 x 60 µL), VW2 buffer (1 x 60 mL), a VeraCode FV/FII Bead Plate with holographically inscribed glass microbeads aliquoted in strip-well plates, a test-specific kit manifest file and sample sheet files (containing test specific outcome specifications and sample plate layout files used to interpret and report genotype results). A magnet plate is also required but sold separately.

Here's a breakdown of the acceptance criteria and the study details for the Illumina VeraCode® Genotyping Test for Factor V and Factor II, based on the provided 510(k) summary:

1. Table of Acceptance Criteria and Reported Device Performance

The device's performance is primarily evaluated through reproducibility (precision) and accuracy (method comparison).

Acceptance Criteria for Reproducibility (Precision):
While explicit numerical acceptance criteria for reproducibility are not stated as "acceptance criteria," the study aimed to demonstrate high agreement for correct calls across different operators, sites, and days. The results presented in the summary show very high percentage agreements and 95% lower confidence bounds (LCB) nearing 100% after retesting, indicating that the implicit acceptance criterion was near-perfect agreement for calling genotypes correctly.

Note: The 95% LCB for homozygous Factor V (70.33%) and Factor II (65.18%) in the accuracy study, while lower than other categories, likely reflect the smaller sample size for these less common genotypes.

2. Sample Size and Data Provenance for the Test Set

• Test Set Sample Size:
  • Reproducibility (Precision) Study: A panel of 15 genomic DNA samples (3 for each of the 5 possible genotypes including Wild Type). Each sample was tested in duplicate once a day for 5 non-consecutive days at each of three sites by two operators. This results in a significant number of replicates (e.g., for Factor V Wild Type, 3 samples * 2 replicates * 5 days * 3 sites * 2 operators = 180 total instances, with slight variations in the tables indicating initial no-calls).
  • Accuracy (Method Comparison) Study: 92 patient samples were accrued at each of the three sites, yielding a total of 276 patient samples. Additionally, each site received two archived DNA samples as positive controls.
• Data Provenance: The report does not explicitly state the country of origin. However, the samples for the accuracy study were "prospectively drawn blood samples" (for interference testing) and "pre-selected or unscreened patients undergoing Factor V testing" (for method comparison), suggesting a combination of prospective and retrospective (archived) samples for the accuracy study. For reproducibility, it uses "genomic DNA samples isolated from blood" and "commercially available cultured cells."

3. Number of Experts and Qualifications for Ground Truth

• Number of Experts: For the accuracy study (method comparison), the ground truth was established by "bi-directional DNA sequencing analysis performed at an independent reference laboratory." The number of individuals/experts involved in this independent sequencing and interpretation is not specified, nor are their specific qualifications (e.g., number of years of experience). However, "bi-directional DNA sequencing" is a well-established and highly accurate method for genotyping, implying expert-level analysis.

4. Adjudication Method for the Test Set

• There appears to be no explicit adjudication method described for resolving discrepancies between the device's results and the ground truth (bi-directional sequencing). The summary reports the raw agreement.
• For the device's own internal "no calls" (samples generating an invalid result), the "no calls" were retested once. This retesting resolved most, but not all, initial "no calls," as seen in the tables (e.g., one FVL Homozygous sample in the accuracy study remained a "no call" after retesting).

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

• No MRMC comparative effectiveness study was done. This device is an in vitro diagnostic (IVD) genetic test, which typically has a standalone performance assessment against a gold standard (like sequencing) rather than evaluating human reader performance with or without AI assistance.

6. Standalone Performance Study (Algorithm Only)

• Yes, a standalone performance study was done. The entire analytical performance section (Precision/Reproducibility and Method Comparison) describes the performance of the device (VeraCode Genotyping Test for Factor V and Factor II on the BeadXpress System, with VeraScan software) as a standalone system. The results of the device were directly compared against the established ground truth (bi-directional sequencing), without human intervention in the interpretation process of the device's output. The software interprets and reports the genotype.

7. Type of Ground Truth Used

• The primary ground truth used for both the reproducibility and accuracy studies was bi-directional DNA sequencing. This is considered a highly reliable and definitive method for determining gene mutations.

8. Sample Size for the Training Set

• The document does not provide information on the sample size used for the training set. As a 510(k) submission for a diagnostic test kit based on established molecular biology principles (PCR, allele-specific primer extension, hybridization), the development of the "algorithm" (the VeraScan software and kit manifest file) would typically rely on well-characterized samples and biochemical parameters rather than a large machine learning training set in the modern sense. The "assay-specific kit manifest file" contains the parameters and cutoffs used to interpret and report genotype results, implying these were established during development.

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

• Similar to the training set sample size, the document does not explicitly detail how ground truth for the training set (development of the kit manifest and software interpretation rules) was established. It's inferable that the development team used well-characterized reference samples (likely with known genotypes confirmed by sequencing or other gold-standard methods) to define the assay parameters, thresholds, and interpretation rules encoded in the kit manifest file that guides the VeraScan software. The "Preliminary passing criteria where all replicates of all genotypes produce the correct result when compared to bi-directional sequencing" mentioned in the detection limit section suggests an iterative process referencing sequencing during development.

Ask a specific question about this device

The eSensor® Thrombophila Risk Test is an in vitro diagnostic for the detection and genotyping of Factor II (Prothrombin) G20210A, Factor V (Factor V Leiden) G1691A and MTHFR (human 5, 10 methylenetetrahydrofolate reductase gene) C677T and A1298C mutations with suspected thrombophilia from isolated genomic DNA obtained from whole blood samples. The test is intended to be used on the eSensor® XT-8 System.

The eSensor® FII-FV Genotyping Test is an in vitro diagnostic for detection and genotyping of Factor II (Prothrombin) G20210A and Factor V (Factor V Leiden) G1691A mutations in patients with suspected thrombophilia from isolated genomic DNA obtained from whole blood samples. The test is intended to be used on the eSensor® XT-8 System.

The eSensor® FV Genotyping Test is an in vitro diagnostic for the detection and genotyping of a single point mutation (G to A at position 1691; also known as Factor V Leiden) of the human Factor V gene (FV; Coagulation Factor V gene) in patients with suspected thrombophilia from isolated genomic DNA obtained from whole blood samples. The test is intended to be used on the eSensor® XT-8 System.

The eSensor® FII Genotyping Test is an in vitro diagnostic for the detection and genotyping of a single point mutation (G to A at position 20210 of the human Factor II gene (FII; prothrombin gene) in patients with suspected thrombophilia, from isolated genomic DNA obtained from whole blood samples. The test is intended to be used on the eSensor® XT-8 System.

The eSensor® MTHFR Genotyping Test is an in vitro diagnostic for the detection and genotyping of point mutations (C to T at position 677) and (A to C at position 1298) of the human 5, 10 methylenetetrahydrofolate reductase gene (MTHFR) in patients with suspected thrombophilia, from isolated genomic DNA obtained from whole blood samples. The test is intended to be used on the eSensor® XT-8 System.

The eSensor® Thrombophila Risk Tests on the eSensor® XT-8 System are in vitro diagnostic devices for performing hybridization and genotyping of multiple mutations and/or polymorphisms in an amplified DNA sample. A single-use, disposable test carridge is used to perform hybridization and genotyping. The cartridge contains an EEPROM chip which transmits the cartridge lot number, expiration date and protocol identity to the XT-8 instrument.

The analysis process for each sample consists of three steps: 1) Genomic DNA isolated from whole blood obtained using EDTA as anti-coagulant is combined with PCR Mix and Taq polymerase enzyme and is subjected to amplification of target sequences by PCR using a thermal cycler. 2) Amplified DNA is treated with exonuclease enzyme to generate single-stranded target DNA. 3) Single-stranded, amplified target DNA is mixed with hybridization and genotyping reagents and transferred to an eSensor® Test cartidge, and the cartridge is inserted in the eSensor® XT-8 Instrument. The instrument controls the circulation of the cartridge to allow hybridization at a controlled temperature and then detects and genotypes the sample by voltammetry.

Genotyping of the test panel polymorphisms is achieved by a sandwich assay principle: 1) Each pair of electrodes contains a different synthetic oligonucleotide capture probe which is complementary to one of the target DNA fragments. 2) The hybridization reagents contain pairs of ferrocene-labeled synthetic oligonucleotide signal probes; one member of each pair is complementary to the major allele sequence of the target polymorphism, while the second member of the pair is complementary to the minor allele sequence. Each member of the probe pair has a ferrocene label with a different oxidation potential for each allele. 3) Single-stranded, amplified target DNA hybridizes to its specific capture probe, and in turn hybridizes to the allele-specific, ferrocene-labeled signal probe. 4) Each electrode of the array is analyzed by voltammetry; the target polymorphism is determined by the location of the electrode containing the capture probe, and the genotype is identified by the ratio of signals from the allele-specific ferrocene labels. The array also includes positive controls to confirm the hybridization reaction and detect non-specific signals.

Upon completion of the test, the EEPROM chip on the cartridge contains information that prevents its re-use with a new sample. The eSensor® XT-8 instrument analyzes the results and provides a report of the test results.

Here's a summary of the acceptance criteria and study details for the eSensor® Thrombophila Risk Test, based on the provided 510(k) summary:

1. Table of Acceptance Criteria and Reported Device Performance

The 510(k) summary does not explicitly state "acceptance criteria" with numerical thresholds prior to presenting the results. However, the performance characteristics, particularly the "Method Comparison" results, implicitly serve as the primary demonstration of meeting performance expectations against a gold standard. For the reproducibility studies, "100% agreement" strongly implies this as an implicit acceptance criterion for internal consistency.

Note on "Implicit Acceptance Criteria": The document consistently reports 100% (final) agreement with DNA sequencing across all categories in the Method Comparison and 100% correct calls for reproducibility studies. This suggests that achieving perfect or near-perfect agreement with the gold standard (DNA sequencing) and internal consistency was the unstated "acceptance criterion" for these performance studies. The 95% LCB (Lower Confidence Bound) values provided in the method comparison table suggest that the statistical power was sufficient to be confident in these high agreement rates, even with sometimes smaller sample sizes for specific mutation types.

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

• Test Set Sample Size:
  • Method Comparison: 219 gDNA samples.
  • Reproducibility (Inter-laboratory, Inter-operator): 5 gDNA samples run in duplicate each day by each of 6 operators (2 operators per site across 3 sites) over 5 days = 5 x 2 x 3 x 5 = 150 test runs. The table states "Samples Tested: 50" per operator, totaling 300 tests. This implies a set of 5 gDNA samples were tested multiple times.
  • Genomic DNA Extraction Reproducibility: 6 whole blood samples tested with 3 different extraction methods = 18 tests.
  • Lot to Lot Reproducibility: 5 genomic DNA samples tested in duplicates using 3 different kit lots = 30 tests.
  • Limit of Detection: 2 genomic DNA samples, each tested 20 times at 5 different concentrations = 2 x 20 x 5 = 200 tests.
• Data Provenance: Not explicitly stated (e.g., country of origin). The document mentions "3 different sites and 1 internal site" for the reproducibility study, indicating multi-site testing within an unspecified geographic region. The "Method Comparison" study uses "gDNA samples extracted from whole blood," but the origin of these samples is not detailed. All data appears to be prospective in the sense of being generated specifically for these performance studies.

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

• Number of Experts: Not applicable in the traditional sense, as the ground truth was established by DNA sequencing, which is a laboratory method, not human expert consensus.
• Qualifications of Experts: Not applicable. DNA sequencing is a technical standard.

4. Adjudication Method for the Test Set

• Adjudication Method: Not applicable. The ground truth (DNA sequencing) is considered the definitive standard. Any discrepancies between the eSensor® test and DNA sequencing would be considered an error by the eSensor® test, not a disagreement among experts requiring adjudication. The document mentions "Final Results" after "additional run for a single no-call" in the Lot to Lot study, suggesting a re-run policy for initial "no-calls" rather than adjudication. Similarly, in the method comparison, "Final Results" reflect cases where initial "no-calls" were resolved, making the "Final Agreement" 100%.

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

• No, an MRMC comparative effectiveness study was not done. This device is a molecular diagnostic test for genotyping, not an imaging diagnostic requiring interpretation by human readers. Therefore, the concept of human readers improving with AI assistance does not apply here.

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

• Yes, a standalone performance study was done. This entire submission focuses on the performance of the eSensor® system (instrument + assay kits) as a standalone diagnostic device. The results are compared directly against DNA sequencing (the gold standard), and the system provides results without real-time human interpretation for genotype determination. Human intervention is limited to sample preparation, loading, and reviewing the automatically generated report.

7. The Type of Ground Truth Used

• The type of ground truth used was DNA sequencing. This is explicitly stated across various sections, most notably under "Genomic DNA Extraction Reproducibility," "Lot to Lot Reproducibility," and "Method Comparison" where "All samples gave 100% correct calls when compared with DNA sequencing."

8. The Sample Size for the Training Set

• The document does not explicitly state a separate "training set" or its sample size. Diagnostic kits like this, especially those based on hybridization and electrochemical detection principles for known mutations, are typically developed and optimized during an R&D phase, and then validated with the performance studies presented. There isn't typically a distinct "training set" in the same way machine learning algorithms have. The pre-market submission focuses on the validation of the finalized device.

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

• Since a separate "training set" is not explicitly mentioned or detailed, the method for establishing ground truth for such a set is also not described. If an internal training or optimization phase utilized samples, it can be inferred that DNA sequencing would have been the likely method for establishing their ground truth, consistent with the validation studies.

Ask a specific question about this device

The Xpert™ HemosIL® Factor II & Factor V Assay is a qualitative in vitro diagnostic genotyping test for the rapid detection of Factor II and Factor V alleles from sodium citrate or EDTA anticoagulated whole blood. The test is performed on the Cepheid GeneXpert® Dx System. This test is intended to provide rapid results for Factor II (G20210A) and Factor V (Leiden) mutations as an aid in the diagnosis in individuals with suspected thrombophilia.

The Cepheid Xpert® HemosIL® Factor II & Factor V Assay is an automated DNA test for detecting Factor II and Factor V normal and mutant alleles directly from sodium citrate or EDTA anticoagulated whole blood specimens. Blood specimens are drawn into either sodium citrate or EDTA anticoagulant tubes. Following brief mixing of the sample, the blood sample and two single-use reagents (Reagent 1 and Reagent 2) that are provided with the assay are transferred to different, uniquely-labeled chambers of the disposable fluidic cartridge (the Xpert HemosIL Factor V cartridge). The user initiates a test from the system user interface and places the cartridge into the GeneXpert® Dx System instrument platform, which performs hands-off real-time, multiplex polymerase chain reaction (PCR) for detection of DNA. In this platform, sample preparation, amplification, and real-time detection are all fully-automated and completely integrated.

The GeneXpert Dx System consists of a GeneXpert instrument, personal computer, a barcode scanner and the multi-chambered fluidic cartridges that are designed to complete sample preparation and real-time PCR for detection of Factor II and Factor V normal and mutant alleles in approximately 30 minutes. Each system has 1 to 16 randomly accessible modules that are each capable of performing separate sample preparation and real-time PCR tests. Each module contains a syringe drive for dispensing fluids, an ultrasonic horn for lysing nuclei, and a proprietary I-CORE® thermocycler for performing real-time PCR and detection.

The Xpert HemosIL Factor II & Factor V Assay includes reagents for the detection of Factor II and Factor V normal and mutant alleles. The primers and probes in the Xpert HemosIL Factor II & Factor V Assay determine the genotype of the Factor II gene (at position 20210) and the Factor V gene (at position 1691).

The test includes a Probe Check Control (PCC) that verifies reagent rehydration, PCR tube filling in the cartridge, probe integrity, and dye stability and an instrument control verifies the instrument is performing properly. Additionally, the sample functions as its own internal control since both normal and mutant gene sequences are detected, and each person tested is expected to have one of these sequence signatures.

Here's a breakdown of the acceptance criteria and the study that proves the device meets them, based on the provided text:

Cepheid Xpert® HemosIL® FII & FV: Acceptance Criteria and Performance Study

The Cepheid Xpert® HemosIL® Factor II & Factor V Assay is a qualitative in vitro diagnostic genotyping test designed to detect Factor II (G20210A) and Factor V Leiden (G1691A) mutations in whole blood, aiding in the diagnosis of individuals with suspected thrombophilia. The primary study presented demonstrates the device's accuracy compared to bi-directional sequencing, which serves as the gold standard.

1. Table of Acceptance Criteria and Reported Device Performance

The document doesn't explicitly define "acceptance criteria" through numerical thresholds but presents performance metrics that implicitly indicate the successful validation of the device. Based on the clinical comparison study, the implicit acceptance criterion is a high agreement with the gold standard (bi-directional sequencing).

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

• Sample Size for Clinical Comparison Study:
  • Factor II: 1018 samples (plus 6 human genomic DNA samples homozygous for Factor II to supplement homozygous sample size).
  • Factor V: 1014 samples (plus 5 human genomic DNA samples homozygous for Factor V to supplement homozygous sample size).
• Data Provenance: The samples were collected in a multi-site investigational study at seven U.S. institutions.
  • The study involved prospective collection of aliquots from routine clinical whole blood specimens (intended for Factor II and/or Factor V testing).
  • Excess DNA from these samples was sent to a contract laboratory for bi-directional sequencing.

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

• The ground truth was established by bi-directional sequencing, which is a laboratory technique rather than expert interpretation. Therefore, the concept of "experts" to establish ground truth in the traditional sense (e.g., radiologists reviewing images) does not directly apply here. The expertise lies in the laboratory personnel performing and interpreting the sequencing results, but specific numbers or qualifications of these individuals are not detailed in the summary.

4. Adjudication Method for the Test Set

• The document primarily describes a direct comparison of the device's results against bi-directional sequencing.
• No explicit adjudication method (e.g., 2+1, 3+1) is mentioned beyond the direct comparison with the gold standard.
• Invalid results are noted. For Factor II, there were 43 invalid results on the first run, reduced to 7 after repeat runs. For Factor V, there were 42 invalid results on the first run, reduced to 7 after repeat runs. These "invalid results" are referred to as "indeterminate" results, meaning they could not be called by the device, but there were no discordant results (where the device definitively called a genotype incorrectly compared to sequencing). This implies that if the device did make a call, it was correct relative to the gold standard.

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

• No MRMC comparative effectiveness study was done. This is a diagnostic test where the device directly provides a result, not an assistive AI tool for human readers.

6. Standalone Performance

• Yes, a standalone (algorithm only without human-in-the-loop performance) study was conducted. The clinical comparison study directly assessed the performance of the Xpert HemosIL Factor II & Factor V Assay (the device) against bi-directional sequencing. The device automatically performs sample preparation, amplification, and real-time detection without human interpretation of the final genotype call. The results in Table 5.2 (Agreement after Repeat Run) represent the standalone performance of the device after initial run and any necessary repeat testing for "indeterminate" results.

7. The Type of Ground Truth Used

• The ground truth used was bi-directional sequencing results, which is considered the gold standard for genetic sequencing.

8. The Sample Size for the Training Set

• The document does not report the sample size for a training set. For an in-vitro diagnostic (IVD) PCR-based assay like this, "training set" doesn't typically apply in the same way it would for machine learning algorithms. The device's primers and probes are designed based on known genetic sequences, and its performance is validated through analytical and clinical studies, not typically through a distinct machine learning training phase on patient data.

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

• As there's no explicitly mentioned "training set" in the context of the device's development as a machine learning model, the method for establishing ground truth for a training set is not applicable. The device's underlying principles are molecular biology and biochemistry (PCR and hybridization probes) rather than learned patterns from a large dataset. The specificity of the probes for Factor II and Factor V mutations defines the "ground truth" the assay is designed to detect.

Ask a specific question about this device

The INFINITI™ System Assay for Factor II & Factor V is an in vitro diagnostic device that consists of reagents and instrumentation which includes polymerase chain reaction (PCR) primers, hybridization matrices, a thermal cycler, an imager, and software for detection and genotyping of Factor II (Prothrombin) G20210A and Factor V Leiden G1691A point mutations in DNA obtained from human blood samples. The INFINITI™ System Assay for Factor II & Factor V is a qualitative assay for use in clinical laboratories upon prescription by the attending physician.

The INFINITI" System Assay for detection and genotyping of Factor II & Factor V is indicated for use as an aid to diagnosis in the evaluation of patients with suspected thrombophilia.

The INFINITI System Assay for Factor II & Factor V is an in vitro diagnostic device which utilizes proprietary film-based microarray technology combined with process automation, reagent management and software technology for the detection and genotyping of the Factor II (Prothrombin) G20210A mutation and the Factor V Leiden G1691A mutation from deoxyribonucleic acid (DNA) isolated from human whole peripheral blood samples.

The INFINITI System Assay for Factor II & Factor V is comprised of the BioFilmChip" Microarray, the Intellipac™ Reagent Module, and the INFINITI Analyzer with the Qmatic" Operating Software.

The BioFilmChip Microarray consists of a polyester film coated with proprietary multi-layer components designed for DNA analysis. The layers have been designed to provide a versatile surface to enhance test performance. There can be up to 240 spots per microarray with each spot representing a different allele. The microarrays are designed to be assay specific.

The Intellipac Reagent Module which acts as a communication link contains up to eight reservoirs that house the test reagents and has an integrated memory chip. The assay protocol resides in this memory chip and upon request is loaded to the INFINITI Analyzer. Information such as expiration date of reagents, volume usage, time of use and operation parameters are archived in the memory chip and appear on the worklist (run report).

The INFINITI Analyzer is an instrument used for clinical multiplex systems intended to measure and sort multiple signals from a clinical sample. The INFINITI Analyzer is designed to measure fluorescence signals of labeled DNA target hybridized to BioFilmChip microarrays. The INFINITI Analyzer automates the Factor II and Factor V assays and integrates all the discrete processes of sample (PCR amplicon) handling, reagent management, hybridization, detection, and results analysis. The assays are processed automatically and read by the built-in confocal microscope. Results are analyzed and presented in numerical and graphical format.

The INFINITI Analyzer has two main components: pipetting and optics modules. A variety of electronic components inside the instrument are used for its operation. These include multiple stepper motors, heating and cooling devices, a barcode reader, a photomultiplier tube, and a camera all connected to USB ports.

Pipetting Module - The pipetting module performs all the operations related to dispensing and aspiration of reagent and processing the amplified sample to be dispensed on the microarray. When the sample has been processed and hybridized to the microarray, it is transferred to the optics module for scanning and reading.

Optics Module - The optics module is a lightproof assembly comprised of a 3-axis stage: camera, lasers, and a photo multiplier tube (PMT). It is the enclosed casement into which the microarray is transported automatically prior to being processed on the stringency station. The optics' stage follows X-Y-Z motions that can be stepped at a very precise rate (2.0 micron per step). Using excitation wavelengths of a 760nm laser diode, the camera takes a 1.2x1.2mm picture for each registration spot of a fluorescent die. Analyses of these pictures allow the location of three registration spots to be determined. With respect to the position of the three registration spots, coordinates of all the bio-spots can be located. While scanning, the stage moves along the Z-axis to focus the chip and the X and Y-axes to locate the individual spots on the microarray.

The INFINITI Analyzer hardware is controlled by the Qmatic™ operating software, which is installed with-in the on-board computer and utilizes a LCD screen display. The INFINITI Analyzer modules are controlled by multitasking real time software. The Omatic "M operating software has a schedule manager that is capable of controlling all operations of the INFINITI Analyzer such as assay protocol, fluid handling, robotics, optical detection and result analysis. Results are available for review via the LCD screen. Management reports include results in numerical and graphical format. The operator can also print the displayed results in tabular form (printer not included with INFINITI Analyzer).

Here's a breakdown of the acceptance criteria and the study information for the INFINITI™ System Assay for Factor II & Factor V, based on the provided 510(k) summary:

1. Table of Acceptance Criteria and Reported Device Performance

The 510(k) summary largely focuses on demonstrating equivalence to predicate devices and detailing performance characteristics rather than explicitly stating pre-defined "acceptance criteria" with specific thresholds for all metrics. However, we can infer the implied acceptance based on the reported results and the comparison to the predicate device.

• Factor V: >95% agreement with predicate device (Roche Factor V Leiden Kit) | - Factor II: 98.6% agreement with predicate
• Factor V: 100.0% agreement with predicate |
  | Limit of Detection (LoD) | Sufficient to detect mutations in typical clinical samples. | 1ng DNA/test. |
  | Assay Precision/Reproducibility | - Chip-to-chip: Low CVs for wild-type calls, 100% correct genotype calls.
• Lot-to-lot: No significant lot-to-lot difference (p>0.05) in RFU, 100% correct genotype calls.
• Day-to-day: Acceptable RFU signal %CV, 100% correct genotype calls. | - Chip-to-chip: CVs for wild-type present calls ranged from 9-12%. All calls were 100% correct.
• Lot-to-lot: Two-way ANOVA on RFU readings did not detect lot-to-lot difference on three of four test runs (p > 0.05). Detected lot-to-lot difference on one test run (0.05 > p > 0.01). Genotype calls were 100% correct.
• Day-to-day: RFU signal %CV ranged from 1.35-14.87 (Day 1), 0.77-19.72 (Day 2), and 0.41-21.2 (Day 3). Genotype calls were 100% correct. |
  | Instrument Reproducibility | - Intra-Instrument: Acceptable %CV, 100% genotype call reproduction.
• Inter-Instrument: Acceptable %CV, 100% correct and reproducible genotype calls. | - Intra-Instrument Reproducibility: %CV using a single chip five times on a single instrument ranged from 0.9 to 28.3%. Genotype calls were 100% reproduced within each instrument.
• Inter-Instrument Reproducibility: %CV using a single chip five times on each of three instruments ranged from 0.5% to 12%. All genotype calls were 100% correct and reproducible.
• Standard Microarray Chip: For three instruments, average %CV for capture probe spots ranged from 3.24% to 4.03%, with ranges per instrument from 1.9-7.5%. |
  | Reagent Stability | Demonstrated stability for adequate shelf life. | - BioFilmChip Microarray: 90 days at RT (25-30 °C)
• Intellipac Reagent Module: 90 days at 4°C
• Amplification Mix: 90 days at 4°C |
  | Interference | No significant interference from common interferents. | No interference with 8mg/dL bilirubin, 70mg/dL cholesterol, and 1333μ/dL heparin. No studies conducted with oral anti-coagulants (no claims made). |
  | Sample Carry-over | No detectable carry-over. | No carry-over detected when a series of positive and negative samples, followed by a "No Template Control," was run six times. |

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

The "test set" here refers to the samples used for the comparative effectiveness study against the predicate device.

• Factor II G20210A mutation: 208 samples
• Factor V Leiden G1691A mutation: 175 samples

The document does not specify the country of origin of the data or whether it was retrospective or prospective.

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

This information is not provided in the given 510(k) summary. The ground truth for the comparison study was based on the results from the predicate devices (Roche Factor II G20210A and Factor V Leiden Kits). It's implied that the predicate devices themselves established the "ground truth" for the samples.

4. Adjudication Method for the Test Set

This information is not provided. The comparison was directly between the new device and the predicate device results. There's no mention of an independent adjudication process for discrepancies.

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

Not Applicable. This device is an in-vitro diagnostic (IVD) assay system and analyzer, not an AI-powered image analysis or diagnostic aid for human readers. Therefore, an MRMC study and analysis of human reader improvement with AI assistance is not relevant to this submission.

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

Yes, the performance characteristics described, such as Limit of Detection, Assay Precision, Instrument Reproducibility, Reagent Stability, Interference, and Sample Carry-over, represent the standalone performance of the INFINITI™ System Assay for Factor II & Factor V. The comparison to the predicate device also assesses its standalone diagnostic performance.

7. The Type of Ground Truth Used

The ground truth for the comparative effectiveness study was established by the predicate devices: the Roche Factor II G20210A Kit and the Roche Factor V Leiden Kit. This means the device's accuracy was assessed by its agreement with these established, FDA-cleared methods.

8. The Sample Size for the Training Set

The document does not specify a separate "training set" size. As this is a molecular diagnostic assay system, the development process typically involves optimizing reagents and conditions rather than training a machine learning algorithm in the conventional sense. The "training" would be more akin to assay development and validation using various known samples.

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

Since a "training set" for a machine learning algorithm is not explicitly defined or used in the context of this traditional IVD assay, the method for establishing its ground truth is not applicable in the same way. The development of the assay would have relied on known positive and negative controls, synthetic DNA, and clinical samples with previously determined genotypes (likely via Sanger sequencing or other established reference methods during the predicate device's development or the assay's R&D phase). This type of information is generally part of the assay development and validation process rather than a separate "training set" section in a 510(k) summary.

Ask a specific question about this device

Ask a specific question about this device