(153 days)
The intended use of the Sysmex R-3500 is as a fully automated reticulocyte analyzer for in vitro diagnostic use in clinical laboratories.
The Sysmex™ R-3500 is an automated reticulocyte analyzer intended for in vitro use in clinical laboratories. The R-3500 provides accurate and precise test results for 8 analysis parameters in whole blood. These include RET%, RET#, RBC, IRF, LFR, MFR, HFR, and PLT. The R-3500 processes approximately 120 samples per hour and displays and prints the data for Reticulocyte number, Reticulocyte percent, Red blood cell count, Immature reticulocyte fraction, fluorescent ratios, and platelets along with representative scattergrams. Sample abnormalities are indicated by abnormal marks, flags, and error messages which appear on the DMS display screen and on the printout. This is an indication that the sample is not within the acceptable range and requires further review and investigation. The R-3500 uses the principle of flow cytometry for reticulocyte analysis. In the instrument, a whole blood sample is automatically aspirated, diluted and stained with a fluorescent dye (Auromine-O). The sample is hydrodynamically focused into a narrow path and passed through a flow cell, where it is illuminated by an Argon laser beam. The cells present in the sample will fluoresce and scatter light to varying degrees. It is the analysis of the intensity of emitted fluorescent light and intensity of scattered light which allows the R-3500 analyzer to detect and enumerate reticulocytes.
Here's a breakdown of the acceptance criteria and study details for the Sysmex™ Automated Reticulocyte Analyzer R-3500 based on the provided text:
1. Acceptance Criteria and Reported Device Performance
The document does not explicitly state pre-defined quantitative acceptance criteria (e.g., "RET% must have an r-value > 0.990"). Instead, it demonstrates the device's performance through correlation studies comparing it to a predicate device. The implicit acceptance criterion is "substantial equivalence" to the predicate device, which is supported by high correlation coefficients (r and r²) and regression equations.
| Parameter | n | r | r² | Regression Equation | Reported Device Performance (Correlation with Predicate Device) |
|---|---|---|---|---|---|
| RET# | 487 | 0.994 | 0.988 | y = 0.965x + 0.001 | Very strong positive correlation |
| RET% | 487 | 0.997 | 0.994 | y = 0.964x + 0.051 | Very strong positive correlation |
| RBC | 486 | 0.998 | 0.997 | y = 1.009x - 0.072 | Very strong positive correlation |
| IRF | 486 | 0.956 | 0.913 | y = 0.948x + 1.409 | Strong positive correlation |
| LFR | 486 | 0.956 | 0.913 | y = 0.948x + 3.819 | Strong positive correlation |
| MFR | 486 | 0.923 | 0.852 | y = 0.917x + 1.433 | Strong positive correlation |
| HFR | 486 | 0.954 | 0.910 | y = 0.940x + 0.490 | Strong positive correlation |
| Platelet | 482 | 0.994 | 0.989 | y = 0.937x + 10.619 | Very strong positive correlation |
2. Sample Size Used for the Test Set and Data Provenance
- Sample Size: The sample size for the test set varied slightly by parameter:
- RET# & RET%: 487 samples
- RBC, IRF, LFR, MFR, HFR: 486 samples
- Platelet: 482 samples
- Data Provenance:
- Country of Origin: Not explicitly stated, but the "research center" where the studies were performed is mentioned. The manufacturer is TOA Medical Electronics Co. in Kobe, Japan, and the importer/distributor is Sysmex™ Corporation in Long Grove, IL, USA. Given the context of seeking FDA clearance, it's likely the studies were conducted to satisfy US regulatory requirements, but the specific geographic origin of the patient samples is not provided.
- Retrospective or Prospective: The text states, "In these studies, the following comparative performance evaluations were conducted using the proposed device and the predicate device to evaluate specimens from apparently healthy individuals and from patients with different pathological conditions which are expected to affect the results for particular parameters." This suggests the samples were collected and then tested on both devices for comparison, which aligns with typical prospective or concurrent comparison study methodology. It doesn't indicate purely retrospective analysis of existing data.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
The document does not mention the use of experts to establish a "ground truth" for the test set. The study compares the performance of the new device (R-3500) against an already cleared predicate device (RAM-1). The predicate device's measurements are effectively treated as the reference for comparison.
4. Adjudication Method for the Test Set
Not applicable. Since the comparison is primarily device-to-device measurements, there is no mention of human adjudication for the test set results. Each device generated its own results, which were then statistically compared.
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 is not an AI/algorithm-assisted human reading device. It's a fully automated analyzer. The study focuses on the comparison between two automated instruments.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) was done
Yes, the study described is a standalone performance evaluation. The Sysmex™ R-3500 is an automated reticulocyte analyzer. The performance data presented (correlation coefficients and regression equations) represent the device's measurements compared directly to those of a predicate automated device. There is no human intervention in the generation of the results being compared.
7. The Type of Ground Truth Used (expert consensus, pathology, outcomes data, etc.)
The "ground truth" in this context is established by the measurements from the predicate device, Sysmex™ SE/RAM-1. The study's objective is to demonstrate substantial equivalence, meaning the new device performs comparably to a legally marketed device.
8. The Sample Size for the Training Set
The document does not provide information about a "training set" or its sample size. This type of 510(k) submission for a diagnostic analyzer typically focuses on demonstrating the performance of the final, released device compared to a predicate, rather than detailing the development and training phases of an algorithm.
9. How the Ground Truth for the Training Set was Established
Not applicable, as no training set information is provided in the document.
§ 864.5200 Automated cell counter.
(a)
Identification. An automated cell counter is a fully-automated or semi-automated device used to count red blood cells, white blood cells, or blood platelets using a sample of the patient's peripheral blood (blood circulating in one of the body's extremities, such as the arm). These devices may also measure hemoglobin or hematocrit and may also calculate or measure one or more of the red cell indices (the erythrocyte mean corpuscular volume, the mean corpuscular hemoglobin, or the mean corpuscular hemoglobin concentration). These devices may use either an electronic particle counting method or an optical counting method.(b)
Classification. Class II (performance standards).