(175 days)
The Urine/CSF Protein assay is used for the quantitative determination of protein in human urine or cerebrospinal fluid (CSF) on the ALCYON™ Analyzer. Identification of urinary protein is used in the diagnosis and treatment of disease conditions such as renal or heart diseases or thyroid disorders, which are characterized by proteinuria or albuminuria. CSF protein measurements are used in the diagnosis and treatment of conditions such as meningitis, brain tumors, and infections of the central nervous system.
Urine/CSF Protein is an in vitro diagnostic assay for the quantitative determination of protein in human urine or cerebrospinal fluid (CSF) on the ALCYON™ Analyzer. The Urine/CSF Protein assay is a clinical chemistry assay using a turbidimetric procedure in which benzethonium chloride is used as the protein denaturing agent. Proteins present in the urine or CSF are denatured by benzethonium chloride resulting in the formation of a fine suspension which is quantitated turbidimetrically at 405 mm. The reagent has been modified to overcome the problem of high concentration (Hook) effect, where very high concentrations of protein in urine can cause an apparent zero or low reading.
Here's an analysis of the provided text regarding the Abbott Urine/CSF Protein assay, framed by the requested information:
1. Table of Acceptance Criteria and Reported Device Performance
The submission does not explicitly list "acceptance criteria" in a typical quantitative sense (e.g., "correlation coefficient must be > 0.95"). Instead, it states that the new device is "substantially equivalent" to the predicate, and this is demonstrated by the reported performance characteristics. The acceptance is implicitly met if the reported performance is considered "acceptable correlation" and "substantially equivalent" to the predicate.
| Performance Metric | Acceptance Criteria (Implicit from Predicate Equivalence) | Reported Device Performance (Abbott Urine/CSF Protein) |
|---|---|---|
| Urine Application | ||
| Correlation Coefficient (vs. Predicate) | Acceptable correlation (e.g., very high) | 0.995 |
| Slope (vs. Predicate) | Close to 1.0 | 0.943 |
| Y-intercept (vs. Predicate) | Close to 0 | 5.146 mg/dL |
| Total %CV (Level 1 Control) | Low variability (e.g., within typical assay expectations) | 5.1% |
| Total %CV (Level 2 Control) | Low variability | 4.5% |
| Linearity Range | Consistent with clinical needs | 10 to 200 mg/dL |
| Limit of Quantitation (Sensitivity) | Consistent with clinical needs | 10 mg/dL |
| CSF Application | ||
| Correlation Coefficient (vs. Predicate) | Acceptable correlation (e.g., very high) | 0.981 |
| Slope (vs. Predicate) | Close to 1.0 | 0.995 |
| Y-intercept (vs. Predicate) | Close to 0 | 1.184 mg/dL |
| Total %CV (Level 1 Control) | Low variability | 2.6% |
| Total %CV (Level 2 Control) | Low variability | 2.1% |
| Linearity Range | Consistent with clinical needs | 10 to 200 mg/dL (Implied from general linearity statement, applied to CSF, although the phrasing is general) |
| Limit of Quantitation (Sensitivity) | Consistent with clinical needs | 10 mg/dL (Implied from general sensitivity statement, applied to CSF) |
2. Sample Size Used for the Test Set and Data Provenance
- Sample Size: The document does not explicitly state the exact number of samples used for the method comparison study (the "test set"). It mentions "comparative performance studies" and "precision studies."
- Data Provenance: The document does not specify the country of origin of the data. It implies the data was collected at Abbott Laboratories or a contract research organization working with them. It is a prospective study as it involves conducting new tests to compare the device against a predicate, rather than analyzing existing datasets.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
This is an in vitro diagnostic (IVD) assay for quantitative protein measurement. The "ground truth" is established by the reference method (the predicate device) or by established analytical techniques. It doesn't involve human expert adjudication in the same way an imaging or pathology device would. Therefore, this question is not directly applicable in a conventional sense for this type of device. The "experts" would be the laboratory personnel performing the assays and analyzing the results according to validated laboratory practices.
4. Adjudication Method for the Test Set
Not applicable. As noted above, this is an IVD assay where quantitative measurements from one device are compared against another, not a diagnostic interpretation requiring adjudication of reader opinions.
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 is an in vitro diagnostic assay, not an AI-assisted diagnostic imaging or pathology system for human readers.
6. If a Standalone (i.e. algorithm only without human-in-the loop performance) Was Done
Yes, in the context of an IVD, the "standalone" performance refers to the device's analytical performance on its own, which is what the linearity, precision, and sensitivity studies assessed. The method comparison also evaluates the device's performance against a predicate as a standalone system.
7. The Type of Ground Truth Used (Expert Consensus, Pathology, Outcomes Data, etc.)
The ground truth for the performance studies was:
- Reference Method/Predicate Device: For method comparison, the Boehringer Mannheim® Urinary/CSF Protein assay on the Hitachi® 717 Analyzer served as the reference standard.
- Known Concentrations: For linearity and sensitivity, materials with known concentrations (e.g., calibrators/standards) were used.
- Control Materials: For precision studies, control materials with expected ranges were used.
8. The Sample Size for the Training Set
Not applicable in the typical sense of machine learning. This is a traditional in vitro diagnostic assay based on a turbidimetric chemical reaction. There isn't a "training set" of data for an algorithm as there would be for an AI/ML device. The "training" of the assay involves optimization of the reagent formulation and reaction conditions, which is a chemical and engineering process, not a data-driven algorithm training.
9. How the Ground Truth for the Training Set Was Established
Not applicable. As mentioned, there isn't a "training set" in the AI/ML context. The optimization of the assay's chemical parameters (reagent formulation, reaction conditions) would be based on fundamental chemical principles and empirical experimentation to achieve desired analytical performance characteristics. The "ground truth" for this optimization would be accurate measurements from established analytical methods during development to ensure the new reagent performs as expected.
§ 862.1635 Total protein test system.
(a)
Identification. A total protein test system is a device intended to measure total protein(s) in serum or plasma. Measurements obtained by this device are used in the diagnosis and treatment of a variety of diseases involving the liver, kidney, or bone marrow as well as other metabolic or nutritional disorders.(b)
Classification. Class II (special controls). The device is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to § 862.9.