(99 days)
The Redi-Test PCP is a qualitative, one step, immunochromatographic competitive assay used to screen human urine for the presence of phencyclidine at a cut off concentration of 25ng/mL. The test is qualitative and provides only a preliminary analytical result, which must be confirmed by an alternate methodology preferably, GC/MS.
The Redi-Test PCP is an immunochromatograpic based one step in vitro test.
The provided text describes the Redi-Test PCP device, its intended use, and a comparison study performed for its 510(k) submission. However, it does not explicitly state "acceptance criteria" as a predefined numerical threshold for performance. Instead, the study aims to demonstrate substantial equivalence to an existing predicate device. The performance is assessed by comparing the new device's results to the predicate device's results.
Here's an analysis of the available information:
1. Table of Acceptance Criteria and Reported Device Performance
| Performance Metric | Acceptance Criteria (Implied by Substantial Equivalence Claim) | Reported Device Performance |
|---|---|---|
| Correlation | >99% correlation with predicate device | >99% correlation |
| Sensitivity | Similar to predicate device (DRI Phencyclidine EIA) | Similar to predicate device |
| Specificity | Similar to predicate device (DRI Phencyclidine EIA) | Similar to predicate device |
| Accuracy | Similar to predicate device (DRI Phencyclidine EIA) | Similar to predicate device |
| Precision | Similar to predicate device (DRI Phencyclidine EIA) | Similar to predicate device |
| Cut-off | 25 ng/mL (to match predicate device) | 25 ng/mL |
Explanation of Implied Acceptance Criteria: The document explicitly states, "The PCP Enzyme Immunoassay and the Redi-Test PCP are substantially equivalent in performance characteristics. The correlation of the two tests was >99%." This implies that the acceptance criterion for the study was to achieve a correlation of >99% and demonstrate similar performance across other key metrics (sensitivity, specificity, accuracy, precision) when compared to the predicate device. For diagnostic devices, demonstrating substantial equivalence to a legally marketed predicate device is a common regulatory pathway.
2. Sample Size Used for the Test Set and Data Provenance
- Sample Size: 100 specimens (50 negative and 50 positive, covering the entire assay range).
- Data Provenance: Not explicitly stated. It is not mentioned if the data was retrospective or prospective, nor the country of origin.
3. Number of Experts Used to Establish Ground Truth for the Test Set and Their Qualifications
- This information is not provided in the text. The "ground truth" for this study was the results obtained from the predicate device, the DRI Phencyclidine Enzyme Immunoassay. The study's goal was to show similarity to this established method, not to establish a new ground truth using experts.
4. Adjudication Method for the Test Set
- This information is not applicable/provided. Since the "ground truth" was the predicate device's results, there was no expert adjudication process for the test set itself in the way it might be applied for, e.g., image interpretation based on multiple expert opinions. The comparison was directly between the Redi-Test PCP and the predicate device's readings.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done
- No, an MRMC comparative effectiveness study was not done. This study is a device-to-device comparison, assessing the performance of the new device against a predicate device, not the improvement of human readers 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 Redi-Test PCP is an in vitro diagnostic (IVD) device that provides a direct result. The comparison was of the device's output (positive/negative for phencyclidine at a specific cut-off) against the output of the predicate device. There is no "human-in-the-loop" component for interpretation described beyond the technician performing the test and reading the result.
7. The Type of Ground Truth Used
- The "ground truth" for comparison was the results obtained from the predicate device, the DRI Phencyclidine Enzyme Immunoassay. The document indicates that both assays require confirmation by an alternate methodology, preferably GC/MS, for definitive results. This suggests that while the predicate device serves as the comparative standard for this submission, the ultimate "true ground truth" for patient management would be GC/MS.
8. The Sample Size for the Training Set
- This information is not provided and is likely not relevant for this type of immunoassay device. Immunoassays typically do not have a "training set" in the machine learning sense. Their performance is inherent to their chemical and biological design. The "testing" referred to is for validation, not for training a model.
9. How the Ground Truth for the Training Set Was Established
- This information is not applicable as there is no "training set" for an immunochromatographic device in the context of this submission.
N/A