(55 days)
The Stat Profile® Prime Plus Analyzer System is indicated for use by healthcare professionals in clinical laboratory settings and for point-of-care usage for quantitative determination of Sodium, Potassium, Chloride, Ionized Calcium, and Ionized Magnesium in heparinized arterial and venous whole blood.
The Stat Profile Prime Plus Analyzer System is a low cost, low maintenance analyzer for hospital laboratory and point-of-care settings. It consists of the analyzer, sensor cartridges, and thermal paper for an onboard printer. Optionally, it provides for reading of barcode labels (such as operator badges and data sheets).
The Stat Profile Prime Plus Analyzer has slots to accommodate two sensor cartridges (Primary and Auxiliary). The analyzer will determine the configuration of the system by detecting which sensor cards are installed.
As with the predicate, the Stat Profile Prime Plus Analyzer is a blood gas, co-oximetry, electrolyte, chemistry, and hematology analyzer with an enhanced test menu and multiple quality control options. Both traditional internal and external quality control is available, as well as an on-board Quality Management System (QMS), and an electronic monitoring approach that insures the analyzer is working properly at all times.
The Stat Profile Prime Plus Analyzer accepts samples from syringes and open tubes. The minimum sample size for analysis is 135 µL.
Sample collection, preparation and application to the same as for the previously cleared predicate. The end user can select which analytes are to be tested in the panel.
Here's a breakdown of the acceptance criteria and study information for the Stat Profile® Prime Plus Analyzer System, based on the provided FDA 510(k) summary:
1. Table of Acceptance Criteria and Reported Device Performance
The document doesn't explicitly state "acceptance criteria" in a quantitative table format. Instead, it presents performance data (method comparison, imprecision) that would be evaluated against established clinical or analytical goals to demonstrate substantial equivalence. The predicate device's performance often serves as the de facto acceptance benchmark.
I will interpret the "Measurement Range" from Table 4 as an implicit acceptance criterion for the device's operational range, and the "Method Comparison Studies" and "Total Imprecision Performance" tables as reported device performance demonstrating equivalence.
| Parameter | Acceptance Criteria (Measurement Range) | Reported Device Performance (Method Comparison: Slope, Intercept, r) | Reported Device Performance (Total Imprecision: Total %CV - Level 4/5/Linearity) | Reported Device Performance (Within-Run Precision: %CV) |
|---|---|---|---|---|
| Sodium (Na) | 80-200 mmol/L | Slope: 0.9964, Intercept: 0.4488, r: 0.9949 | Level 4: 0.6%, Level 5: 0.8%, Linearity: 1.2% | Samples 1-7: 0.22% - 0.67% |
| Potassium (K) | 1.0-20.0 mmol/L | Slope: 1.0158, Intercept: -0.0678, r: 0.9993 | Level 4: 2.2%, Level 5: 1.9%, Linearity: 1.5% | Samples 1-7: 0.00% - 2.66% |
| Chloride (Cl) | 50-200 mmol/L | Slope: 0.9963, Intercept: 0.4416, r: 0.9971 | Level 4: 0.6%, Level 5: 0.6%, Linearity: 0.9% | Samples 1-7: 0.00% - 0.67% |
| Ionized Calcium (iCa) | 0.4-10.8 mg/dL | Slope: 0.9820, Intercept: 0.0239, r: 0.9871 | Level 4: 2.1%, Level 5: 2.7%, Linearity: 1.9% | Samples 1-7: 0.40% - 1.13% |
| Ionized Magnesium (iMg) | 0.24-3.65 mg/dL | Slope: 1.0020, Intercept: -0.0021, r: 0.9910 | Level 4: 4.4%, Level 5: 6.5%, Linearity: 5.4% | Samples 1-7: 0.52% - 2.63% |
2. Sample Size Used for the Test Set and Data Provenance
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Method Comparison Studies (Test Set):
- Sample Sizes:
- Na: 432 samples (18 altered samples)
- K: 435 samples (21 altered samples)
- Cl: 434 samples (20 altered samples)
- iCa: 434 samples (20 altered samples)
- iMg: 426 samples (13 altered samples)
- Data Provenance: The study was a Point-of-Care (POC) study conducted at 3 POC sites including a Cardiothoracic Intensive Care Unit (CTICU), an Emergency Department (ED), and a Respiratory Therapy Lab (RT). The data provenance is described as comparing "results obtained by trained Healthcare Professionals to results obtained by POC personnel on the same specimens using the same analyzer." The specimens were either quality control materials or discarded blood gas specimens.
- Retrospective or Prospective: Not explicitly stated, but the description of "comparing results obtained by trained Healthcare Professionals to results obtained by POC personnel" suggests a prospective collection or at least a controlled, concurrent comparison for the purpose of the study. It's not described as a retrospective analysis of existing patient data.
- Sample Sizes:
-
Total Imprecision Performance (Test Set):
- The estimates were obtained from different POC personnel running 3 levels of Quality Control/Linearity Materials in duplicate each day for a total of 20 runs on 3 analyzers. (Implies a substantial number of measurements, but the exact N for each measurement type is not detailed beyond "20 runs").
-
Within-Run Whole Blood Precision (Test Set):
- Each precision run consisted of ten (10) replicate measurements. A total of five (5) different native samples and two (2) altered samples were evaluated at each site. This was done by a minimum of two (2) point-of-care operators at each of the three (3) POC sites, for a total of nine (9) operators.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
The study compares the performance of the Stat Profile® Prime Plus Analyzer System against existing laboratory methods (referred to as "Lab" in Table 1) and its own predicate device.
For the Method Comparison Studies, the "ground truth" or reference method is the "Lab" result, which would typically be generated by a validated, high-accuracy laboratory analyzer. The document does not specify individual human experts or their qualifications for establishing this ground truth; rather, it refers to the "Lab" as the reference. For clinical laboratory devices, the "ground truth" is usually the result from a recognized reference standard method or a highly accurate laboratory instrument rather than individual expert consensus.
For the Imprecision studies, the "ground truth" is typically the measured mean of repeated measurements, and the accuracy is relative to a known value for Quality Control materials. Again, this doesn't involve human experts establishing ground truth in the way it might for imaging studies.
4. Adjudication Method for the Test Set
This type of diagnostic device (blood analyzer) does not typically involve human adjudication in the same way as, for example, image-based diagnostic systems. The method comparison studies compare the device's quantitative output to that of a reference laboratory method. No specific adjudication method like "2+1" or "3+1" is mentioned or applicable here.
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
No, a Multi-Reader Multi-Case (MRMC) comparative effectiveness study was not done. This type of study is relevant for AI-based diagnostic systems where human readers interpret medical images or data. The Stat Profile® Prime Plus Analyzer System is a quantitative in vitro diagnostic device, not an AI-assisted diagnostic tool that supports human interpretation in that manner. The study focused on demonstrating the analytical performance and equivalence of the device to a predicate and laboratory methods.
6. If a Standalone (i.e. algorithm only without human-in-the loop performance) Was Done
The device itself is a standalone analyzer that measures parameters and produces results. The performance studies (Method Comparison, Imprecision) evaluate the device's standalone analytical performance. Although POC personnel operate the device, the data presented (slopes, intercepts, r-values, %CV) reflects the intrinsic performance of the algorithm/hardware combination (the "device") in generating quantitative measurements, rather than human interpretation. So, yes, the performance metrics reported are for the device operating in a standalone capacity (as a measurement instrument).
7. The Type of Ground Truth Used
- Method Comparison Studies: The ground truth for the method comparison studies was obtained from a reference laboratory method or a "Lab" analyzer. This implies comparison to established, presumably accurate, laboratory instrumentation with well-defined performance characteristics.
- Imprecision and Within-Run Precision Studies: The ground truth for these studies relies on the known concentration values of quality control materials and the statistical analysis of repeated measurements to determine the reproducibility and variability of the device.
8. The Sample Size for the Training Set
The document does not describe the device as employing a machine learning or AI algorithm that requires a distinct "training set" in the conventional sense of AI/ML development. The device uses established "Ion-Selective Electrode (ISE)" technology and measurement algorithms. Therefore, there is no mention of a "training set" for an AI model.
9. How the Ground Truth for the Training Set Was Established
As there is no mention of a "training set" for an AI model, this question is not applicable. The measurement principles are based on known electrochemical properties rather than learned patterns from a training dataset.
§ 862.1665 Sodium test system.
(a)
Identification. A sodium test system is a device intended to measure sodium in serum, plasma, and urine. Measurements obtained by this device are used in the diagnosis and treatment of aldosteronism (excessive secretion of the hormone aldosterone), diabetes insipidus (chronic excretion of large amounts of dilute urine, accompanied by extreme thirst), adrenal hypertension, Addison's disease (caused by destruction of the adrenal glands), dehydration, inappropriate antidiuretic hormone secretion, or other diseases involving electrolyte imbalance.(b)
Classification. Class II.