(140 days)
The FasTraQ Automated Analyzer in coniunction with the PrePaQ Total hCG Cartridge is intended for use as an aid in the early detection of pregnancy where rapid, quantitative results in the emergency department or where other rapid diagnostics are required. The assay is to be used with patient whole blood samples.
The Quantech PrePaQ Total hCG Test Cartridge is intended for use with the FasTraQ Automated Analyzer to provide rapid, quantitative measurement of human chorionic gonadotropin (hCG) in whole blood for the determination of pregnancy. The Analyzer and hCG Cartridge combine ease of use and rapid turnaround time with laboratory-quality performance and reliability. The FasTraQ System is designed for use by non-laboratory medical professionals in emergency departments, STAT or central laboratories.
The PrePaQ Cartridge in coniunction with the FasTraQ Automated Analyer is use to quantitate hCG in whole blood using surface plasmon resonance (SPR). The Quantech PrePaQ Total ß-hCG assay is based on the principle of two site, or sandwich immunoassay in combination with SPR surface mass measurement. Each PrePaQ cartridge contains a solid phase ß-hCG monoclonal antibody immobilized onto a gold surface. An anti-alpha hCG polyclonal antibody conjugated to alkaline phosphatase is attached to the antigen to form the sandwich. An enhancing solution is used to further increase the mass on the surface.
The provided text describes the Quantech FasTraQ Automated Analyzer and PrePaQ Total hCG Test Cartridge, intended for rapid, quantitative measurement of human chorionic gonadotropin (hCG) in whole blood for pregnancy determination. The device's performance is compared to predicate devices like the Bayer Centaur and Abbott AxSym.
Here's an analysis of the acceptance criteria and the study that proves the device meets them, based on the provided text:
1. Table of Acceptance Criteria and Reported Device Performance
The document does not explicitly state formal "acceptance criteria" with numerical thresholds for regulatory approval. Instead, it presents various performance characteristics and implicitly compares them to predicate devices or established laboratory standards to demonstrate "substantial equivalence." The "acceptance criteria" are implied by the performance of the predicate devices and general expectations for clinical laboratory assays.
| Performance Characteristic | Implicit Acceptance Criteria (Inferred) | Reported Device Performance (Quantech PrePaQ Total ß-hCG Assay) |
|---|---|---|
| Dilution Linearity/Parallelism | Acceptable linearity across the measuring range, indicating the assay accurately measures increasing concentrations of analyte. | Average percent of expected was 111%. (Implies good linearity as it's close to 100%, though specific range for "acceptable" isn't given). |
| Recovery | Acceptable percentage of analyte recovered, demonstrating accuracy of measurement. | After correcting for endogenous hCG, the average recovery was 105%. (Generally considered good recovery). |
| Analytical Sensitivity (Limit of Detection) | Detect hCG at clinically relevant low concentrations. (Predicate device Centaur's 2.8 mIU/mL provides an indirect benchmark for comparison in clinical range, though analytical sensitivity isn't directly compared here). | Calculated analytical sensitivity: 2.5 mIU/mL. (This is a low detection limit, suggesting good sensitivity). |
| Precision (INTERASSAY) | Acceptable variability (low % C.V.) across different runs and days, reflecting reliability and reproducibility. | Mean hCG concentrations (with % C.V.): 57.1 (10.6%), 216.9 (8.1%), and 553.8 (5.9%) mIU/mL for low, medium, and high pools, respectively. |
| Precision (TOTAL IMPRECISION) | Acceptable overall variability, accounting for all sources of variation. | Mean hCG concentrations (with % C.V.): 57.2 (13.6%), 216.9 (12.8%), and 553.7 (9.0%) mIU/mL for low, medium, and high pools, respectively. (These CVs are acceptable for quantitative immunoassays, especially at lower concentrations). |
| Interfering Substances | No significant interference from common physiological substances at elevated levels. | Percent recovery of hCG was determined to be acceptable in all three solutions (hemoglobin, bilirubin, triglycerides at 10x highest expected physiological concentration); no interference noted. (Indicates robustness against common interferences). |
| Hook Effect | No erroneously low results for very high analyte concentrations. | No high dose hook effect observed up to at least 100,000 mIU/mL. (Critical for clinical safety, as falsely low results could lead to misdiagnosis). |
| Normal Range (Negative Pregnancy) | Performance at and below the accepted value for determination of pregnancy (greater than 25 mIU/ml) should be similar to predicate device, with no false positives in healthy individuals. | 95% normal range: 8.2 mIU/mL (Quantech) vs. 2.8 mIU/mL (Centaur). No false positive results in apparently healthy individuals. 100% agreement with predicate device (Centaur) in this range. (Demonstrates acceptable performance for negative pregnancy determination and agreement with predicate). |
| Patient Sample Correlation | High correlation with established, commercially available methods (predicate devices). | Internal paired sample comparison with Bayer Centaur (predicate device): correlation coefficient of 0.97 (slope = 0.67, intercept = 1.47). External paired sample comparison with Abbott AxSym: correlation coefficient of 0.93 (slope = 0.89, intercept = -1.7992). (High correlation coefficients demonstrate strong agreement with existing, approved methods, supporting substantial equivalence). |
2. Sample Sizes Used for the Test Set and Data Provenance
- Dilution Linearity/Parallelism: "Whole blood samples were separately spiked with intact hCG and serially diluted." The exact number of samples is not specified, but it refers to "samples" in plural.
- Recovery: Not specified, but likely the same samples as for linearity or similar spiked samples.
- Analytical Sensitivity: "Multiple duplicates of whole blood zero samples were assayed." The exact number is not specified.
- Precision: "Three pools in triplicate on different days" for interassay precision.
- Interfering Substances: "A whole blood pools" spiked with interfering substances.
- Hook Effect: "Samples well beyond the standard curve range." Number not specified.
- Normal Range: "Apparently healthy individuals." The number is not specified.
- Patient Sample Correlation: "Human samples with values distributed throughout the quantitative range of the Quantech hCG assay." The number is not specified.
Data Provenance: The document generally refers to "whole blood samples" and "human samples." There is no specific mention of the country of origin. The studies appear to be prospective in nature, as they involve testing the Quantech device's performance under various conditions.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Their Qualifications
The document does not mention the use of experts to establish a "ground truth" in the context of diagnostic interpretation. For quantitative assays like hCG, the "ground truth" for validation is typically the reference method (e.g., predicate device assays) or known concentrations of analytes (e.g., spiked samples, traceable calibrators). The studies rely on quantitative measurements and statistical comparisons rather than expert interpretation of images or clinical cases.
4. Adjudication Method for the Test Set
Not applicable. As this is a quantitative clinical laboratory assay, there is no "adjudication method" in the sense of reconciling differences in expert interpretations for a test set. The performance is assessed through statistical comparisons to predicate devices or known values.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done
No, an MRMC study was not done. MRMC studies are typically performed for devices that involve human interpretation of medical images or data (e.g., radiologists reading scans). This device is an automated in vitro diagnostic assay, and its performance is evaluated objectively by comparing its quantitative output to other assays or known concentrations, not by assessing human reader improvement with or without AI assistance.
6. If a Standalone (i.e. algorithm only without human-in-the-loop performance) Was Done
Yes, the studies described are standalone performance evaluations of the Quantech FasTraQ Automated Analyzer and PrePaQ Total hCG Assay. The data presented ("Dilution Linearity," "Recovery," "Analytical Sensitivity," "Precision," "Interfering Substances," "Hook Effect," "Normal Range," "Patient Sample Correlation") all refer to the intrinsic analytical performance of the device itself, without human intervention in the result generation or initial interpretation directly impacting the reported performance metrics. The intended use allows for "non-laboratory medical professionals," suggesting ease of use, but the analytical performance described is independent of the user's interpretive skill.
7. The Type of Ground Truth Used
The "ground truth" in this context is established by:
- Known concentrations: For studies like dilution linearity, recovery, analytical sensitivity, and hook effect, the "ground truth" is typically the known amount of hCG added or expected in the samples. Calibrators and controls with certified concentrations would also serve as a form of ground truth.
- Predicate device results: For the patient sample correlation and comparison of normal range, the results obtained from the Bayer Centaur (predicate device) and Abbott AxSym serve as the comparative "ground truth" to demonstrate substantial equivalence.
- Clinical consensus/established values: The "accepted value for determination of pregnancy (greater than 25 mIU/ml)" serves as a clinical ground truth benchmark.
8. The Sample Size for the Training Set
The document does not mention a "training set" or "training data" in the context of the device's development. This is typical for traditional in vitro diagnostic devices based on established immunoassay principles, where "training" (in the machine learning sense) is not directly applicable. The device's parameters and algorithms (e.g., for data acquisition and reduction) would be developed and validated through internal R&D processes, not through a 'training set' of patient data in the way a machine learning algorithm would be.
9. How the Ground Truth for the Training Set Was Established
Not applicable, as a "training set" in the machine learning sense is not described or implied for this traditional in vitro diagnostic device.
§ 862.1155 Human chorionic gonadotropin (HCG) test system.
(a)
Human chorionic gonadotropin (HCG) test system intended for the early detection of pregnancy —(1)Identification. A human chorionic gonadotropin (HCG) test system is a device intended for the early detection of pregnancy is intended to measure HCG, a placental hormone, in plasma or urine.(2)
Classification. Class II.(b)
Human chorionic gonadotropin (HCG) test system intended for any uses other than early detection of pregnancy —(1)Identification. A human chorionic goadotropin (HCG) test system is a device intended for any uses other than early detection of pregnancy (such as an aid in the diagnosis, prognosis, and management of treatment of persons with certain tumors or carcinomas) is intended to measure HCG, a placental hormone, in plasma or urine.(2)
Classification. Class III.(3)
Date PMA or notice of completion of a PDP is required. As of the enactment date of the amendments, May 28, 1976, an approval under section 515 of the act is required before the device described in paragraph (b)(1) may be commercially distributed. See § 862.3.