(71 days)
The CEDIA Theophylline Assay is a homogeneous enzyme immunoassay for the in vitro assay of theophylline in human serum and plasma. Measurements are used in the diagnosis and treatment of theophylline overdose and in monitoring levels of theophylline to ensure proper therapy.
The CEDIA® Theophylline Assay is an in-vitro homogeneous enzyme immunoassay used for the measurement of theophylline in serum and plasma. It is based on competitive binding concepts employing theophylline labeled enzymatic fragments (β-galactosidase) competing with sample theophylline for the theophylline -specific antibody. Using recombinant DNA techniques, the β-galactosidase molecule has been split into two totally inactive polypeptide subunits called enzyme acceptor and enzyme donor. Theophylline has been covalently linked to the enzyme donor in a manner that does not prevent spontaneous reassociation of the subunits to yield active β-galactosidase enzyme. Theophylline -specific antibody, by binding to the Theophylline derivative on the enzyme donor will inhibit enzyme reassociation, thereby regulating the level of β-galactosidase formed. The amount of enzyme formed is proportional to the amount of theophylline as monitored by the hydrolysis of the substrate chlorophenol red-β-D-galactopyranoside (CPRG).
Here's a breakdown of the acceptance criteria and study information for the CEDIA® Theophylline Assay on the BM/Hitachi 704, based on the provided text:
Acceptance Criteria and Device Performance
This 510(k) summary focuses on demonstrating substantial equivalence of the CEDIA® Theophylline Assay on the BM/Hitachi 704 to the predicate device, the CEDIA® Theophylline Assay on the BM/Hitachi 911. The acceptance criteria are implicitly derived from the performance characteristics of the predicate device, as the new device aims to achieve similar or better performance. The summary explicitly compares the new device's performance against the predicate.
| Performance Characteristic | Acceptance Criteria (Implicit, based on predicate: BM/Hitachi 911) | Reported Device Performance (On BM/Hitachi 704) |
|---|---|---|
| Sensitivity (LDD) | 0.8 µg/mL | 0.8 µg/mL |
| Precision | ||
| Low Control Within-Run %CV | 3.3% | 5.5% |
| Mid Control Within-Run %CV | 1.9% | 2.8% |
| High Control Within-Run %CV | 1.3% | 2.1% |
| Low Control Total %CV | 5.1% | 6.4% |
| Mid Control Total %CV | 2.4% | 3.2% |
| High Control Total %CV | 2.0% | 2.5% |
| Method Comparison (vs. BM/Hitachi 911) | ||
| Slope | (Ideally close to 1.0) | 1.09 |
| Intercept | (Ideally close to 0.0) | -0.60 |
| Correlation | (Ideally close to 1.0) | 0.996 |
Note: For precision, the acceptance criteria are implicit. The reported performance for the BM/Hitachi 704 is compared directly to the BM/Hitachi 911, and the slight differences are presented for review to demonstrate substantial equivalence, rather than strict "pass/fail" thresholds against a predefined numerical acceptance. The overall correlation for method comparison is a key indicator of agreement, with 0.996 being excellent.
Study Information
Due to the nature of this submission (a 510(k) for an in vitro diagnostic device), many of the typical questions for AI/ML-based medical devices are not directly applicable. This is a chemical assay, not an AI algorithm.
-
Sample size used for the test set and the data provenance:
- Test Set Sample Size: 126 serum samples for the method comparison study.
- Data Provenance: Not explicitly stated, but typically for in vitro diagnostic studies, these are clinical samples usually obtained from a clinical lab setting. The country of origin is not specified, nor is whether the data was retrospective or prospective.
-
Number of experts used to establish the ground truth for the test set and the qualifications of those experts: Not applicable. For an in vitro diagnostic assay, the "ground truth" for the test set samples is typically established by comparative measurement against a reference method or validated primary method (in this case, the predicate device and a Fluorescence Polarization Immunoassay). Human expert consensus is not a method for establishing the ground truth for quantitative chemical measurements.
-
Adjudication method for the test set: Not applicable. Adjudication methods like 2+1 or 3+1 are used for subjective interpretations (e.g., image reading), not for objective quantitative measurements from an assay.
-
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 not an AI/ML-based device that aids human readers. It is a laboratory assay.
-
If a standalone (i.e., algorithm only without human-in-the-loop performance) was done: The device is a standalone assay. Its performance is evaluated purely on its analytical capabilities (precision, sensitivity, method comparison) without human interpretation as part of its core function, beyond running the test and interpreting the numerical result.
-
The type of ground truth used:
- For Method Comparison: The "ground truth" was established by:
- Measurements from the Predicate Device: CEDIA Theophylline Assay on the BM/Hitachi 911.
- Measurements from a Fluorescence Polarization Immunoassay (for the BM/Hitachi 911 comparison).
- For Precision: Ground truth is based on the known concentrations of control samples (Low, Mid, High) and the statistical analysis of repetitive measurements.
- For Method Comparison: The "ground truth" was established by:
-
The sample size for the training set: Not applicable. This is an immunoassay, not an AI/ML device that requires a training set.
-
How the ground truth for the training set was established: Not applicable, as there is no "training set" for this type of device.
§ 862.3880 Theophylline test system.
(a)
Identification. A theophylline test system is a device intended to measure theophylline (a drug used for stimulation of the muscles in the cardiovascular, respiratory, and central nervous systems) in serum and plasma. Measurements obtained by this device are used in the diagnosis and treatment of theophylline overdose or in monitoring levels of theophylline to ensure appropriate therapy.(b)
Classification. Class II.