(94 days)
HiChem® ISE Electrolyte Buffer, when used in conjunction with the HiChem® ISE Electrolyte Reference, HiChem® CO2 Acid Reagent, HiChem® CO2 Alkaline Buffer, HiChem® Wash Concentrate, and HiChem® Calibration Standards, is intended for the quantitative determination of sodium, chloride, and total CO2 in serum and plasma, and sodium, potassium and chloride in urine, and chloride in cerebrospinal fluid on the Beckman® CX® and CX® DELTA Systems. On appropriately configured SYNCHRON® CX® DELTA Systems, HiChem® ISE Electrolyte Buffer will also determine calcium in serum, plasma and urine.
Sodium results are for 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 antidiurelic hormone secretion, or other diseases involving electrolyte balance. Potassium results are used to monitor electrolyte imbalance in the diagnosis and treatment of diseases and conditions characterized by low or high blood potassium levels. Chloride results are used in the diagnosis and treatment of electrolyte and metabolic disorders such as cystic fibrosis and diabetic acidosis. Carbon dioxide results are used in the diagnosis and treatment of numerous and potentially senous disorders associated with changes in the body's acid-base balance. Calcium results are used in the diagnosis and treatment of parathyroid diseases, chronic renal disease and tetany (intermittent muscular contractions or spasms).
This reagent is intended for professional use only.
HiChem® ISE Electrolyte Buffer is intended for the quantitative determination of sodium, potassium, chloride, and total CC2 in serum and plasma, and sodium, potassium and chloride in urine, and chloride in cerebrospinal fluid on the Beckman® SYNCHRON® CX® and CX® DELTA Systems. On appropriately configured SYNCHRON® CX® DELTA Systems. HiChem® ISE Electrolyte Buffer will also determine calcium in serum, plasma and urine.
The provided document describes the safety and effectiveness information for the HiChem® ISE Electrolyte Buffer, which is intended for the quantitative determination of various electrolytes in biological fluids. The study aims to demonstrate substantial equivalence to a predicate device, the SYNCHRON® CX® Systems ISE Electrolyte Buffer Kit.
1. Table of Acceptance Criteria and Reported Device Performance
The acceptance criteria for "substantial equivalence" are implicitly demonstrated through performance comparable to a legally marketed predicate device. This is evaluated through precision studies (imprecision, expressed as %CV) and patient comparison studies (linear regression analysis, including slope 'b', intercept 'a', and correlation coefficient 'r'). The device is considered to meet acceptance criteria if its performance is comparable to or better than the predicate device across various analytes and sample types.
Precision Study Acceptance Criteria (Implicit for Substantial Equivalence):
The HiChem® Reagents should show similar or better precision (lower %CV) compared to the Beckman® Reagents for all analytes and sample types.
| Analyte | Sample | HiChem® Reagents - Total %CV (Reported) | Beckman® Reagents - Total %CV (Predicate) | Acceptance Met? (HiChem ≤ Beckman) |
|---|---|---|---|---|
| Calcium in mg/dL | Serum 1 | 1.9% | 2.0% | Yes |
| Serum 2 | 1.0% | 1.1% | Yes | |
| Serum 3 | 1.1% | 1.1% | Yes | |
| Urine 1 | 3.9% | 4.2% | Yes | |
| Urine 2 | 2.8% | 2.8% | Yes | |
| Chloride in mmol/L | Serum 1 | 1.4% | 1.5% | Yes |
| Serum 2 | 1.0% | 1.0% | Yes | |
| Serum 3 | 1.1% | 0.8% | No (HiChem higher) | |
| Urine 1 | 1.9% | 1.9% | Yes | |
| Urine 2 | 2.4% | 2.2% | No (HiChem higher) | |
| CSF 1 | 1.4% | 1.5% | Yes | |
| CSF 2 | 1.5% | 1.5% | Yes | |
| Potassium in meq/L | Serum 1 | 1.3% | 1.4% | Yes |
| Serum 2 | 0.8% | 0.8% | Yes | |
| Serum 3 | 1.1% | 0.8% | No (HiChem higher) | |
| Urine 1 | 1.0% | 1.2% | Yes | |
| Urine 2 | 1.4% | 1.7% | Yes | |
| Sodium in meq/L | Serum 1 | 1.3% | 1.5% | Yes |
| Serum 2 | 0.7% | 0.8% | Yes | |
| Serum 3 | 0.9% | 0.8% | No (HiChem higher) | |
| Urine 1 | 3.9% | 4.7% | Yes | |
| Urine 2 | 1.2% | 1.5% | Yes | |
| Total CO2 in mmol/L | Serum 1 | 3.0% | 2.9% | No (HiChem higher) |
| Serum 2 | 1.6% | 1.7% | Yes | |
| Serum 3 | 2.1% | 1.5% | No (HiChem higher) |
Patient Comparison Study Acceptance Criteria (Implicit for Substantial Equivalence):
The linear regression parameters (slope 'b', intercept 'a', and correlation coefficient 'r') for HiChem® vs. Beckman® results should ideally be close to b=1, a=0, and r=1, indicating close agreement between the two reagent systems. There are no explicit numerical thresholds stated, but typical acceptance ranges for such studies would be, for example, a slope between 0.95 and 1.05 and a correlation coefficient (r) above 0.975 (or 0.98), though these are not formally defined in the document.
| Analyte | Specimen | Unit | n | Slope 'b' (Reported) | Intercept 'a' (Reported) | Correlation 'r' (Reported) | Acceptance Met? (Implicit: b near 1, a near 0, r near 1) |
|---|---|---|---|---|---|---|---|
| Calcium | Serum/Plasma | mg/dL | 160 | 0.989 | 0.0 | 0.985 | Yes (appears good) |
| Urine | mg/dL | 74 | 1.007 | -0.2 | 0.998 | Yes (appears very good) | |
| Chloride | Serum/Plasma | mmol/L | 160 | 0.988 | 1.0 | 0.935 | Moderately good correlation, intercept slightly high. |
| Urine | mmol/L | 78 | 1.049 | -5.1 | 0.999 | Very good correlation, but intercept is somewhat large. | |
| CSF | mmol/L | 44 | 1.024 | -3.4 | 0.985 | Good correlation, but intercept is somewhat large. | |
| Potassium | Serum/Plasma | meq/L | 160 | 0.969 | 0.13 | 1.000 | Very good (perfect correlation reported). |
| Urine | meq/L | 80 | 0.993 | 0.01 | 1.000 | Very good (perfect correlation reported). | |
| Sodium | Serum/Plasma | meq/L | 160 | 0.930 | 9.1 | 0.938 | Lower correlation and larger intercept. |
| Urine | meq/L | 78 | 1.000 | -0.3 | 1.000 | Very good (perfect correlation reported). | |
| Total CO2 | Serum/Plasma | mmol/L | 160 | 0.949 | 1.2 | 0.953 | Good, but slightly lower correlation and higher intercept. |
Summary of Acceptance: While there are a few instances where the HiChem® Reagents show slightly higher %CV in the precision study, these differences are generally small. The patient comparison study generally shows good agreement (high 'r' values and 'b' values close to 1), although some intercepts ('a') are noticeable, and the correlation for Chloride and Sodium in Serum/Plasma is somewhat lower than other analytes. Overall, the provided data aims to demonstrate "substantial equivalence", and the FDA's clearance (K992844) indicates that these results were considered acceptable.
2. Sample Size Used for the Test Set and the Data Provenance
-
Precision Study Test Set:
- For calcium, chloride, potassium, sodium, and total CO2, 60 replicates (n=60) were performed for most serum and urine samples with HiChem reagents, and 59 or 58 for some CSF and urine samples. The same applies to Beckman reagents.
- Data collection occurred twice per day in triplicate over ten different days (totaling 30 days time frame).
- Data Provenance: Not explicitly stated, but the study was conducted using the Beckman® SYNCHRON® CX® DELTA System. It is likely that the controls and pools used were standard laboratory materials, not patient samples specifically.
-
Patient Comparison Study Test Set:
- Calcium: Serum/Plasma (n=160), Urine (n=74)
- Chloride: Serum/Plasma (n=160), Urine (n=78), CSF (n=44)
- Potassium: Serum/Plasma (n=160), Urine (n=80)
- Sodium: Serum/Plasma (n=160), Urine (n=78)
- Total CO2: Serum/Plasma (n=160)
- Data Provenance: "Serum, plasma, cerebrospinal fluid and urine specimens, collected from adult patients" were used. The country of origin for these patients is not specified, but it's implied to be retrospective as they are "collected specimens."
3. Number of Experts Used to Establish the Ground Truth for the Test Set and the Qualifications of Those Experts
This document describes the performance of a diagnostic reagent kit, not a device requiring human interpretation of results. The "ground truth" for the precision study would be the true concentration of the analytes in the controlled samples (controls, urine pools). For the patient comparison study, the "ground truth" for evaluating the HiChem® device's performance is the results obtained from the predicate Beckman® reagent system. No human experts are used for establishing ground truth in this type of in vitro diagnostic device study; the "ground truth" is established by the reference method (the predicate device) or by the known concentrations of quality control materials.
4. Adjudication Method for the Test Set
Not applicable. This is an in vitro diagnostic (IVD) device measuring quantitative analytes. Results are numerical and compared directly to a predicate device's numerical results or to known concentrations for quality control. There is no human interpretation or adjudication involved in determining the "truth."
5. If a multi-reader multi-case (MRMC) comparative effectiveness study was done
No, an MRMC study was not done. This type of study is relevant for imaging devices or other diagnostics where human readers interpret results, often with and without AI assistance, to assess the impact of the AI on diagnostic accuracy or efficiency. This document concerns an in vitro diagnostic reagent kit, which does not involve human readers in the interpretation of raw data.
6. If a standalone (i.e., algorithm only without human-in-the-loop performance) was done
Yes, implicitly. The performance data presented for the HiChem® ISE Electrolyte Buffer is its "standalone" performance when run on the specified Beckman® SYNCHRON® CX® and CX® DELTA Systems. The device itself is a reagent and operates automatically once specimens are introduced to the analyzer. The results are generated directly by the analytical system using the reagent, without human intervention in the result calculation or interpretation beyond operating the instrument and ensuring quality control.
7. The type of ground truth used
- Precision Study: The ground truth for evaluating imprecision is the mean concentration of the analyte within the control material or urine pools, and then the variability (SD, %CV) around that mean is calculated. The "true" concentration of these controls/pools serves as a reference.
- Patient Comparison Study: The ground truth for evaluating agreement is the results obtained from the predicate device (Beckman® reagents). The HiChem® results are compared against these predicate results via linear regression to demonstrate substantial equivalence, not against an external, independent "gold standard" truth like pathology or patient outcomes.
8. The Sample Size for the Training Set
The document describes a 510(k) submission for a new reagent kit, demonstrating its performance. It does not utilize machine learning or AI that would require a distinct "training set" in the computational sense. The "training" for such a system would typically refer to the internal development and calibration of the reagent and the analytical device itself, which is not detailed here. The studies described (precision, patient comparison) are validation studies.
9. How the ground truth for the training set was established
As there is no "training set" in the conventional AI/ML sense for this type of IVD device, this question is not applicable. The device's calibration and performance characteristics would have been established by the manufacturer through rigorous internal development and testing, likely using certified reference materials and established analytical methods.
§ 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.