(229 days)
The OScout™ Lab is a quantitative multi-parameter automated hematology analyzer intended for in vitro diagnostic use in screening patient populations 18 years and older found in clinical laboratories and point-of-care (POC) settings. The QScout Lab is used with the QScout RLD test to enumerate and classify the following parameters in venous K2/K3EDT A whole blood:
- White blood cell count (WBC)
- · Neutrophils (NEUT#)
- · Lymphocytes (LYMPH#)
- · Monocytes (MONO#)
- · Eosinophils (EOS#)
- · Basophils (BASO#)
- · Immature Granulocytes (IG#)
- · Percent Neutrophils (NEUT%)
- Percent Lymphocytes (LYMPH%)
- · Percent Monocytes (MONO%)
- · Percent Eosinophils (EOS%)
- · Percent Basophils (BASO%)
- · Percent Immature Granulocytes (IG%)
- · Neutrophil to Lymphocyte Ratio (NLR)
The QScout™ system is intended for in vitro diagnostic use in screening patient populations 18 years and older found in clinical laboratories and point-of-care (POC) settings. It includes the QScout Lab analyzer, the QScout RLD (Rapid Leukocyte Differential) test, software, and handheld barcode scanner. The QScout system reports white blood cell count and neutrophil to lymphocyte ratio and enumerates and classifies six white blood cell types including immature granulocytes.
The QScout RLD test includes a microfluidic chamber of predetermined volume containing a dried reagent of organic compounds to stain and fluoresce white blood cells. Once venous whole blood is transferred to the QScout RLD test, white blood cells mix with the reagent. The QScout RLD test is inserted into the QScout Lab, a quantitative multi-parameter automated hematology analyzer, where an optical imaging system takes images of the test chamber. A machine vision algorithm identifies cells from the images in real time. When analysis is complete, the results are displayed on the screen and can be printed.
Here's a breakdown of the acceptance criteria and the study proving the device meets them, based on the provided FDA 510(k) summary for the QScout Lab and QScout RLD.
Note: The provided document primarily focuses on demonstrating substantial equivalence to a predicate device through various performance studies (method comparison, repeatability, reproducibility, detection limits, linearity, interference, stability, and flagging studies for clinical sensitivity). It does not explicitly define a single, overarching "acceptance criteria" table with pre-defined thresholds for all parameters, but rather implicitly defines acceptance through CLSI guidelines and successful outcomes of the tests. The "reported device performance" is the results shown in the tables.
1. Table of Acceptance Criteria and the Reported Device Performance
As noted above, a single clear table of acceptance criteria with numerical thresholds is not presented. Instead, acceptance is demonstrated by meeting the "pre-defined acceptance criteria" for various studies, often referencing CLSI standards. The reported device performance is provided in the tables and textual summaries of each study.
Here's a synthesized table based on common analytical performance metrics found in the document:
| Metric Type / Parameter | Implicit Acceptance Criteria (based on study outcome & CLSI) | Reported Device Performance (as per document) |
|---|---|---|
| Method Comparison (vs. Predicate) | Correlation, slope, and bias met pre-defined acceptance criteria (implicit adherence to CLSI EP09c, H20-A2, H26-A2) | All parameters met pre-defined acceptance criteria (e.g., WBC Slope: 1.008 (0.998, 1.020), Pearson's r: 0.996; NEUT# Slope: 0.976 (0.963, 0.987), Pearson's r: 0.985; MONO# Slope: 1.100 (1.050, 1.146), Pearson's r: 0.907; etc. - see Table 1) |
| Repeatability (Precision) | Acceptable Coefficient of Variation (CV%) and Standard Deviation (SD) around medical decision levels and within reference range (implicit adherence to CLSI H26-A2) | See Table 2 for detailed pooled CV% results (e.g., WBC |
§ 864.5220 Automated differential cell counter.
(a)
Identification. An automated differential cell counter is a device used to identify one or more of the formed elements of the blood. The device may also have the capability to flag, count, or classify immature or abnormal hematopoietic cells of the blood, bone marrow, or other body fluids. These devices may combine an electronic particle counting method, optical method, or a flow cytometric method utilizing monoclonal CD (cluster designation) markers. The device includes accessory CD markers.(b)
Classification. Class II (special controls). The special control for this device is the FDA document entitled “Class II Special Controls Guidance Document: Premarket Notifications for Automated Differential Cell Counters for Immature or Abnormal Blood Cells; Final Guidance for Industry and FDA.”