(59 days)
The ACON BAR II One Step Barbiturates Test Strip and the ACON BAR II One Step Barbiturates Test Device are rapid chromatographic immunoassays for the qualitative detection of Barbiturates in urine at a cutoff concentration of 300 ng/mL. These tests are used to provide only a preliminary analytical result. All positive test results obtained with these devices must be confirmed by another test method, preferably GC/MS analysis. They are intended for healthcare professionals including professionals at point-of-care sites.
The ACON BAR II One Step Barbiturates Test Strip and the ACON BAR II One Step Barbiturates Test Device are competitive binding, lateral flow immunochromatographic assays for the qualitative screening of Barbiturates in a urine sample. The test is based on the principle of antibody immunochemistry. It utilizes the mouse monoclonal antibody to selectively detect elevated levels of Barbiturates and its metabolite in urine at a cutoff concentration of 300 ng/mL. These tests can be performed without the use of an instrument. A drug-positive urine specimen will not generate a colored-line in the designated test region, while a negative urine specimen or a urine specimen containing Barbiturates at the concentration below the cutoff level will generate a colored-line in the test region. To serve as a procedural control, a coloredline should always appear at the control region, indicating that proper volume of specimen has been added and membrane wicking has occurred.
Here's an analysis of the provided text regarding the acceptance criteria and the study that proves the device meets those criteria:
Device: ACON BAR II One Step Barbiturates Test Strip & Device
The information provided describes a qualitative immunoassay for the detection of Barbiturates in urine. The primary acceptance criteria appear to be substantial equivalence to an existing FDA-cleared device and satisfactory agreement with Gas Chromatography/Mass Spectrometry (GC/MS) analysis, particularly around the 300 ng/mL cutoff concentration.
1. Table of Acceptance Criteria and Reported Device Performance
The document doesn't explicitly state quantitative acceptance criteria prior to presenting the results. However, based on the discussion of "substantial equivalency" and the reported data, the implicit acceptance criteria are high levels of agreement with both a predicate device and the gold standard (GC/MS).
| Acceptance Criteria (Implicit) | Reported Device Performance (ACON BAR II One Step Barbiturates Test Strip / Device) |
|---|---|
| High Positive Agreement with FDA-cleared Barbiturates Test | > 99% (120/120) with 95% CI (97% - 100%) |
| High Negative Agreement with FDA-cleared Barbiturates Test | 87% (156/180) with 95% CI (81% - 91%) |
| High Overall Agreement with FDA-cleared Barbiturates Test | 92% (276/300) with 95% CI (88% - 95%) |
| High % Agreement (Positive) with GC/MS (near cutoff) | 99% (141/142) with 95% CI (96% - 99%) |
| High % Agreement (Negative) with GC/MS (near cutoff) | 98% (155/158) with 95% CI (95% - 99%) |
| High Total Agreement with GC/MS | 98.67% (296/300) with 95% CI (97% - 99%) |
| Satisfactory performance by healthcare professionals at POC | 97% (262/270) of cases interpreted correctly by POL staff |
| Comparable POL study results to trained lab technician | 97% (87/90) for trained lab technician |
2. Sample Size Used for the Test Set and Data Provenance
- Sample Size for Test Set: 300 clinical urine specimens.
- Data Provenance: "Clinical urine specimens" (retrospective, implies real-world samples from a clinical setting). The country of origin is not explicitly stated.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
The ground truth was established by Gas Chromatography/Mass Spectrometry (GC/MS) analysis. GC/MS is a laboratory analytical method, not directly performed by "experts" in the sense of human readers/interpreters in this context. It's a gold standard objective chemical analysis. Therefore, the concept of "number of experts" and their "qualifications" as human interpreters is not applicable here. GC/MS analysis is typically performed by trained laboratory technicians or chemists.
4. Adjudication Method for the Test Set
The adjudication method described is comparison against GC/MS analysis. There is no mention of an adjudication process among multiple human experts. The ACON BAR II test results were compared directly against the GC/MS results.
5. If a Multi Reader Multi Case (MRMC) Comparative Effectiveness Study was Done
No, a Multi Reader Multi Case (MRMC) comparative effectiveness study was not done in the sense of comparing human readers with and without AI assistance. The study compared the device (a rapid diagnostic test, not an AI) against a predicate device and GC/MS.
There was a "POL Study" (Point-of-Care) that indicated:
- Personnel at different doctor's offices with various educational backgrounds and working experience could perform the tests properly and interpret results correctly in most cases (97%, 262/270).
- These results were comparable to those obtained from a trained lab technician (97%, 87/90).
This study evaluated user performance of the device, not the device's ability to assist human readers in a diagnostic task where the device itself is an AI application.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) was Done
Yes, the primary accuracy evaluations against the predicate device and GC/MS were standalone performance studies of the ACON BAR II tests (Strip and Device). The tests are rapid chromatographic immunoassays that yield a visual result (presence or absence of a colored line). While a human interprets the visual result, the "performance" figures (agreement percentages) are based on the device's output compared to the reference methods, effectively a standalone evaluation of the device's analytical capability.
7. The Type of Ground Truth Used
The primary ground truth used was Gas Chromatography/Mass Spectrometry (GC/MS) analysis. This is considered a highly objective and definitive chemical analysis method often referred to as the "gold standard" for drug detection.
8. The Sample Size for the Training Set
The document does not explicitly mention a "training set" or a separate dataset used for the development or training of the device. Given that this is an immunoassay, not a machine learning algorithm, the concept of a "training set" as understood in AI/ML is not directly applicable. These devices are typically developed through iterative chemical and engineering optimization.
9. How the Ground Truth for the Training Set Was Established
As mentioned above, the concept of a "training set" with established ground truth, as defined for AI/ML, does not apply to this immunoassay device. The device's underlying principles are based on antibody-antigen interactions, developed through chemical and biological research and optimization.
§ 862.3150 Barbiturate test system.
(a)
Identification. A barbiturate test system is a device intended to measure barbiturates, a class of hypnotic and sedative drugs, in serum, urine, and gastric contents. Measurements obtained by this device are used in the diagnosis and treatment of barbiturate use or overdose and in monitoring levels of barbiturate to ensure appropriate therapy.(b)
Classification. Class II (special controls). A barbiturate test system is not exempt if it is intended for any use other than employment or insurance testing or is intended for Federal drug testing programs. The device is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in § 862.9, provided the test system is intended for employment and insurance testing and includes a statement in the labeling that the device is intended solely for use in employment and insurance testing, and does not include devices intended for Federal drug testing programs (e.g., programs run by the Substance Abuse and Mental Health Services Administration (SAMHSA), the Department of Transportation (DOT), and the U.S. military).