FDA 510(k) Search - By Innolitics (SaMD and AI Experts)

XN CHECK BF is used for control and calibration verification of Sysmex XN series (XN-10, XN-20) analyzers. It is not, however, intended for actual calibration of these analyzers. Assayed parameters include:

WBC-BF (103/μl), RBC-BF (10°/μl), MN# (103/μl), PMN# (103/μl), MN% (%), PMN% (%), TC-BF# (103/ul)

Device Description

XN CHECK™ BF is an in-vitro diagnostic product that contains the following: stabilized red blood cell component(s) and stabilized white blood cell component(s) in a preservative medium. The product is packaged in polypropylene plastic vials with screw caps containing 3 ml. The vials will be packaged in (4) welled vacuum formed clamshell container with the product information sheet / assay sheet. The product must be stored at 2 - 8° C.

AI/ML Overview

The provided document is a 510(k) summary for the Streck XN CHECK™ BF device, which is a hematology quality control mixture. It describes the device, its intended use, and compares it to a predicate device (Cell-Chex Auto-[K053362](https://510k.innolitics.com/search/K053362)). The document also includes information about the tests conducted to establish performance.

Based on the provided text, here's an analysis of the acceptance criteria and study information:

**1. Table of Acceptance Criteria and Reported Device Performance**

The document does not explicitly state quantitative acceptance criteria in a table format for performance metrics. Instead, it makes general statements about the study results. The primary "performance" assessed for this type of device (a quality control mixture) relates to its stability and consistency, and its substantial equivalence to a predicate device.

| Performance Metric          | Acceptance Criteria (Implied)                                    | Reported Device Performance                                    |
|-----------------------------|------------------------------------------------------------------|----------------------------------------------------------------|
| Open-Vial Stability         | Stability for 30 days (matching predicate device)                | "Same" as predicate (30 days)                                  |
| Closed-Vial Stability       | Stability for at least 75 days (matching predicate device)       | 84 days (exceeds predicate's 75 days)                          |
| Precision Performance       | Consistency and reproducibility                                  | "consistently reproducible"                                    |
| Substantial Equivalence     | Performance comparable to the predicate device (Cell-Chex Auto)  | "substantially equivalent to the predicate product"            |
| Safety and Effectiveness    | Device is safe and effective for its intended use                | "XN CHECK™ BF is a safe and effective product, which fulfills its intended use" |

**2. Sample Size Used for the Test Set and Data Provenance**

The document does not specify the exact sample sizes used for the Open-Vial Stability, Closed-Vial Stability, or Precision Performance tests. It simply states that "The following studies were conducted to establish performance of XN CHECK™ BF."

Data Provenance: Not explicitly stated, but these types of studies for in-vitro diagnostic controls are typically conducted internally by the manufacturer using fresh device samples, often in a laboratory setting. It is not mentioned whether the data is retrospective or prospective, but stability studies inherently involve prospective evaluation over time.

**3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts**

This information is not applicable and therefore not provided in the document. For a hematology quality control mixture, "ground truth" isn't established by human expert consensus on interpretations of images or clinical data. Instead, the "truth" is derived from the established values of the control material, measured on high-precision reference instruments or by defined methods. The stability and precision studies would involve comparing measurements over time and across different runs/lots, rather than expert interpretation.

**4. Adjudication Method for the Test Set**

Not applicable. Adjudication methods (like 2+1, 3+1) are used to resolve discrepancies in human readings or interpretations, typically in studies involving imaging or clinical diagnosis. This device is a quality control material, and its performance is assessed through quantitative laboratory measurements, not through subjective human interpretation requiring adjudication.

**5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was done, and if so, what was the effect size of how much human readers improve with AI vs without AI assistance**

Not applicable. This device is an in-vitro diagnostic control, not an AI-powered diagnostic tool for human readers. Therefore, an MRMC study and a human-in-the-loop comparison with AI assistance are not relevant to its evaluation.

**6. If a standalone (i.e., algorithm only without human-in-the-loop performance) was done**

Not applicable. This device is a physical quality control material for analyzers, not a software algorithm. Therefore, "standalone algorithm performance" is not a relevant concept for this product. Its performance is inherent to its chemical and biological composition and how it performs on specific analyzers.

**7. The Type of Ground Truth Used**

The concept of "ground truth" as typically applied in AI/diagnostic imaging studies (e.g., pathology, clinical outcomes, expert consensus) does not directly apply here. For a quality control material like XN CHECK™ BF, the "ground truth" is established by:

*   **Reference Methodology:** The manufacturing process and characterization of the control material itself, which targets specific analyte concentrations (e.g., WBC-BF, RBC-BF counts).
*   **Assayed Values:** The expected range of values for each parameter (WBC-BF, RBC-BF, etc.) determined through rigorous testing on reference instruments and methods, often by the manufacturer. These assayed values serve as the "true" or target values against which the control material's performance (stability, precision) is measured when run on user instruments.
*   **Comparison to Predicate Device:** Substantial equivalence implies that the performance characteristics (including stability and precision of measurements) are comparable to an already legally marketed and accepted control material, the Cell-Chex™ Auto.

**8. The Sample Size for the Training Set**

Not applicable. This device is not an AI algorithm that requires a "training set" in the conventional machine learning sense. The "training" here would be the manufacturing process and initial characterization of the control material.

**9. How the Ground Truth for the Training Set was Established**

Not applicable, as there is no "training set" in the context of an AI algorithm. The "truth" for this control material is established through its manufacturing specifications and extensive testing to determine its assayed values and stability characteristics, often using validated laboratory methods and reference instruments.

Summary

Regulation Number and Section

§ 864.8625 Hematology quality control mixture.

(a)
Identification. A hematology quality control mixture is a device used to ascertain the accuracy and precision of manual, semiautomated, and automated determinations of cell parameters such as white cell count (WBC), red cell count (RBC), platelet count (PLT), hemoglobin, hematocrit (HCT), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC).(b)
Classification. Class II (special controls). Except when intended for use in blood components, the device is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in § 864.9.