(265 days)
The Alinity c ICT (Integrated Chip Technology) is used for the quantitation of sodium, potassium, and chloride in human serum, plasma, or urine on the Alinity c analyzer.
Sodium measurements 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.
Potassium measurements are used to monitor electrolyte balance in the diagnosis and treatment of diseases conditions characterized by low or high blood potassium levels.
Chloride measurements are used in the diagnosis and treatment of electrolyte and metabolic disorders such as cystic fibrosis and diabetic acidosis.
The Alinity c ICT Sample Diluent is a reagent kit containing Reagent 1 (Buffer). It is used with the Alinity c ICT Serum Calibrator and Alinity c ICT Urine Calibrator on the Alinity c analyzer. The system utilizes ion-selective electrodes (ISE) for sodium, potassium, and chloride, which develop an electrical potential across membranes selective to each ion. This voltage is compared to calibrator voltages and converted into ion concentration. The methodology is Ion-selective electrode diluted (Indirect) and the detection is Potentiometric.
The provided document describes the Alinity c ICT Sample Diluent, a device used for the quantitation of sodium, potassium, and chloride in human serum, plasma, or urine. The document mainly focuses on non-clinical performance studies to demonstrate substantial equivalence to a predicate device, rather than a clinical study with acceptance criteria in the traditional sense of diagnostic accuracy or reader performance.
Here's an analysis of the provided information based on your requested criteria:
The studies presented are primarily analytical performance studies (precision, linearity, interference, method comparison, and tube type equivalency) to demonstrate the device's accuracy and reliability compared to a predicate device. The acceptance criteria are internal, predefined thresholds for these analytical performance characteristics.
1. Table of Acceptance Criteria and Reported Device Performance
| Performance Characteristic | Analyte & Matrix | Acceptance Criteria | Reported Device Performance |
|---|---|---|---|
| Precision | Sodium (Serum) | Within-laboratory (total) imprecision ≤ 1.5% CV (for 131-153 mmol/L) | Max 0.7% CV (125 mmol/L), Max 0.7% CV (190 mmol/L) |
| Potassium (Serum) | Within-laboratory (total) imprecision ≤ 2.7% CV (for 4.0-6.0 mmol/L) | Max 1.7% CV (1.6 mmol/L), Max 0.7% CV (9.4 mmol/L) | |
| Chloride (Serum) | Within-laboratory (total) imprecision ≤ 2.0% CV (for 89.0-99.0 mmol/L) | Max 1.0% CV (55 mmol/L), Max 0.8% CV (132 mmol/L) | |
| Sodium (Urine) | Within-laboratory (total) imprecision ≤ 3.0% CV (for 79.0-181.0 mmol/L) | Max 2.9% CV (21 mmol/L), Max 1.1% CV (92 mmol/L) | |
| Potassium (Urine) | Within-laboratory (total) imprecision ≤ 3.0% CV (for 31.0-84.0 mmol/L) | Max 2.4% CV (1.7 mmol/L), Max 0.8% CV (58.2 mmol/L) | |
| Chloride (Urine) | Within-laboratory (total) imprecision ≤ 1.8% CV (for 79.0-218.0 mmol/L) | Max 1.6% CV (24 mmol/L), Max 1.0% CV (193 mmol/L) | |
| Interference | Sodium (Serum) | Bias > 2% considered significant interference | Not susceptible within specified interferent levels |
| Potassium (Serum) | Bias > 10% considered significant interference | Not susceptible within specified interferent levels | |
| Chloride (Serum) | Bias > 10% considered significant interference | Not susceptible within specified interferent levels | |
| Sodium (Urine) | Bias > 10% considered significant interference | Not susceptible within specified interferent levels | |
| Potassium (Urine) | Bias > 10% considered significant interference | Not susceptible within specified interferent levels | |
| Chloride (Urine) | Bias > 10% considered significant interference | Not susceptible within specified interferent levels | |
| Method Comparison | Na, K, Cl (Serum) | Acceptable correlation, slope, and intercept (relative to predicate) | Correlation 1.00, Slope ~1.00, Intercept ~0.00 (all) |
| Na, K, Cl (Urine) | Acceptable correlation, slope, and intercept (relative to predicate) | Correlation 1.00, Slope ~1.00, Intercept ~0.00 (all, minor variations) | |
| Linearity | All analytes/matrices | Meets limits of acceptable performance | Demonstrated linearity across specified ranges |
| Measuring Interval | All analytes/matrices | Meets limits of acceptable performance for linearity, imprecision, and bias | Measuring intervals are defined and stated |
| Tube Type Equivalency | All analytes/matrices | Demonstrate suitability across acceptable tube types | Deemed acceptable for listed tube types |
2. Sample Sizes Used for the Test Set and Data Provenance
The document does not explicitly state the country of origin for the data or whether the studies were retrospective or prospective, for patient samples. The studies are described as "Within-Laboratory Precision" and "Method Comparison," implying they were conducted in a controlled laboratory setting.
- Precision Studies (Test Set):
- Serum Samples: For Sodium, Potassium, and Chloride assays, each control level (3 levels) typically had
n=243ton=252measurements per control lot. For patient panels,n=485ton=498measurements were performed. - Urine Samples: For Sodium, Potassium, and Chloride assays, each control level (2 levels) typically had
n=240measurements per control lot. For patient panels,n=479ton=480measurements were performed.
- Serum Samples: For Sodium, Potassium, and Chloride assays, each control level (3 levels) typically had
- Method Comparison (Test Set):
- Sodium (Serum):
n=141 - Sodium (Urine):
n=101 - Potassium (Serum):
n=122 - Potassium (Urine):
n=107 - Chloride (Serum):
n=120 - Chloride (Urine):
n=112 - Data Provenance: "Human serum and urine specimens that spanned the measuring interval of the assay were evaluated." The specific origin (e.g., country) is not mentioned. These are likely prospective samples collected for testing.
- Sodium (Serum):
- Interference Studies (Test Set): Not explicitly stated, but typically these studies use spiked samples or samples with naturally elevated interferents.
- Tube Type Equivalency (Test Set): Samples were collected from a minimum of
40 donors.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Their Qualifications
This type of device (in-vitro diagnostic for electrolyte measurement) does not typically involve human experts establishing ground truth in the way medical imaging or pathology devices do. The "ground truth" for these analytical studies is established by:
- Reference Methods: For calibrator concentrations, "flame photometry calibrated against NIST Standard Reference Material" and "titration with silver calibrated against NIST Standard Reference Material" were used.
- Predicate Device: For method comparison, the "ARCHITECT ICT Sample Diluent Sodium, Potassium, and Chloride" is used as the comparator method, implying its results are considered the established values for comparison.
- Known Concentrations: For precision, linearity, and interference studies, samples are often prepared with known concentrations or spiked with specific substances.
Therefore, the concept of "experts establishing ground truth" as in qualitative diagnostic interpretation is not applicable here.
4. Adjudication Method for the Test Set
Not applicable for this type of analytical performance study. Adjudication methods like 2+1 or 3+1 are used for qualitative assessments, typically when human interpretations are being compared, or when there's disagreement among experts on a ground truth.
5. Multi Reader Multi Case (MRMC) Comparative Effectiveness Study
No. This is an analytical performance study for an in-vitro diagnostic instrument component, not a diagnostic imaging or AI-driven interpretive device. Therefore, a MRMC comparative effectiveness study involving human readers with and without AI assistance is not relevant.
6. Standalone (Algorithm Only) Performance Study
Yes, implicitly. The entirety of the reported Nonclinical Performance (precision, linearity, interference, method comparison, and tube type equivalency) represents the standalone performance of the Alinity c ICT Sample Diluent device on the Alinity c analyzer. There is no "human-in-the-loop" aspect to the measurement of electrolyte concentrations by this automated system.
7. Type of Ground Truth Used
- Reference Methods: NIST Standard Reference Materials, flame photometry, and titration with silver were used to establish the ground truth for calibrator concentrations.
- Comparator (Predicate) Device: The ARCHITECT ICT Sample Diluent was used as the comparator for method comparison studies.
- Known Concentrations/Spiked Samples: For precision, linearity, and interference studies, samples with known or precisely prepared concentrations were used.
8. Sample Size for the Training Set
This document does not describe the development of an algorithm that would require a separate "training set" in the context of machine learning. The device is an in-vitro diagnostic reagent and system based on established ion-selective electrode technology. Its performance is evaluated through analytical studies, not by training a model on a dataset.
9. How the Ground Truth for the Training Set Was Established
Not applicable. As explained in point 8, there is no "training set" in the machine learning sense for this device.
§ 862.1170 Chloride test system.
(a)
Identification. A chloride test system is a device intended to measure the level of chloride in plasma, serum, sweat, and urine. Chloride measurements are used in the diagnosis and treatment of electrolyte and metabolic disorders such as cystic fibrosis and diabetic acidosis.(b)
Classification. Class II.