(76 days)
Abbott STREP A Controls are qualitative control materials intended for use in test systems to monitor substantial reagent failure and procedural errors. Specifically, Abbott STREP A Controls are intended for use as external controls in Abbott Rapid Immunoassays for the qualitative detection of Group A Streptococcal antigen.
The provided documents describe the clearance of Abbott STREP A Controls (K972182) as external controls for Abbott Rapid Immunoassays for the qualitative detection of Group A Streptococcal antigen. The primary study presented focuses on demonstrating substantial equivalence to a predicate device (K922490) and establishing the Relative Limit of Detection for the associated Strep A assays.
Here's a breakdown of the requested information based on the provided text:
1. Table of Acceptance Criteria and Reported Device Performance
For the Abbott STREP A Controls (K972182):
| Acceptance Criteria (for controls) | Reported Device Performance |
|---|---|
| For Positive Controls: Consistently produce correct positive results across assay lots. | Two lots of Strep A positive control gave 100% correct results across three lots of each of the Abbott Rapid Group A Strep Immunoassays (TestPack Strep A, TestPack Plus Strep A, TestPack Plus Strep A with OBC, TestPack Plus Strep A with OBC II). |
| For Negative Controls: Consistently produce correct negative results across assay lots. | Four lots of Strep A negative controls were tested and gave 100% correct results across three lots of TestPack Plus Strep A with OBC. |
| Relative Limit of Detection (of associated assays): Specific dilutions of Strep A Stock should consistently produce low-level positive results. | - TPSA: 1:667 dilution of Strep A Stock consistently produced positive results. |
- TP+SA & TP+SA OBC: 1:1000 dilution of Strep A Stock consistently produced positive results.
- TP+SA OBC II: 1:500 dilution of Strep A Stock consistently produced positive results.
(Note: This is not an acceptance criterion for the controls themselves, but rather for the assays they are designed to control. The controls are then designed relative to these limits.) |
2. Sample Size Used for the Test Set and Data Provenance
- Positive Controls: Two lots of Strep A positive control were tested. Each positive control lot was tested with three lots of each of the four Abbott Rapid Immunoassays (TPSA, TP+SA, TP+SA OBC, TP+SA OBC II).
- Negative Controls: Four lots of Strep A negative controls were tested with three lots of TestPack Plus Strep A with OBC.
- Relative Limit of Detection Study: Two lots of Strep A Stock were used. For each dilution level, two replicates were assayed on three lots of reaction discs for each of the four assays. This involves multiple individual test runs (2 stock lots * various dilutions * 2 replicates * 3 assay lots * 4 assays).
- Data Provenance: The documents do not explicitly state the country of origin. Given the Abbott Laboratories address provided (Abbott Park, IL, USA) and the submission to the FDA, it is highly likely the study was conducted in the United States. The studies appear to be prospective in nature, designed specifically to demonstrate the performance of the controls and the assays.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
Not applicable for this type of device and study. The "ground truth" for these tests is based on the known composition of the positive (containing Strep A antigen) and negative (not containing Strep A antigen) controls, and the established reactivity of the assays to known concentrations of Strep A. The results were "visually read at EOA [End of Assay]" but no mention of expert consensus or qualifications for reading these specific assays is provided, as they are likely standard visual interpretations based on product instructions.
4. Adjudication Method for the Test Set
Not applicable. The results were "visually read at EOA for all assays." There's no mention of a complex adjudication process as the readings are expected to be straightforward positive or negative interpretations, confirming the presence or absence of a visual signal.
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 device is a diagnostic control material, not an AI-assisted diagnostic tool.
6. If a Standalone (i.e. algorithm only without human-in-the-loop performance) was done
Not applicable. The "device" in question is a control material. The assays it controls still involve a human reading the visual results.
7. The Type of Ground Truth Used
The ground truth used is based on the known concentration and presence/absence of Group A Strep antigen in the prepared Strep A Stock dilutions and the positive/negative control materials. The Strep A Stock itself is defined as a "suspension of phenol-killed Strep A organisms." Thus, it's essentially a reference standard/known concentration approach.
8. The Sample Size for the Training Set
Not applicable in the conventional sense for an AI/algorithm. This device is a control material, and the studies performed are for its validation and the determination of the Relative Limit of Detection of the associated assays. There is no "training set" for an algorithm.
9. How the Ground Truth for the Training Set was Established
Not applicable, as there is no "training set" for an algorithm. The "ground truth" for the performance studies (as described in point 7) was established by the precise formulation of the Strep A Stock and control materials with known concentrations or presence/absence of Strep A antigen.
§ 862.1660 Quality control material (assayed and unassayed).
(a)
Identification. A quality control material (assayed and unassayed) for clinical chemistry is a device intended for medical purposes for use in a test system to estimate test precision and to detect systematic analytical deviations that may arise from reagent or analytical instrument variation. A quality control material (assayed and unassayed) may be used for proficiency testing in interlaboratory surveys. This generic type of device includes controls (assayed and unassayed) for blood gases, electrolytes, enzymes, multianalytes (all kinds), single (specified) analytes, or urinalysis controls.(b)
Classification. Class I (general controls). Except when intended for use in donor screening tests, quality control materials (assayed and unassayed) are exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in § 862.9.