Search Results

The Elecsys PTH Immunoassay is for the in vitro quantitative determination of intact parathyroid hormone in human serum and plasma as an aid in the differential diagnosis of hypercalcemia and hypocalcemia and can be used intraoperatively. The Elecsys PTH STAT Immunoassay is for the in vitro quantitative determination of intact parathyroid hormone in human serum and plasma for the differential diagnosis of hypercalcemia and hypocalcemia and can be used intraoperatively. The electrochemiluminescence immunoassay "ECLIA" is intended for use on the indicated Elecsys and cobas e immunoassay analyzers.

The Elecsys PTH and Elecsys PTH STAT Assays are two step sandwich immunoassay with streptavidin microparticles and electrochemiluminescence detection. Results are determined using a calibration curve that is generated specifically on each instrument by a 2 point calibration and a master curve provided with the reagent bar code.

The provided text details a 510(k) summary for the "Elecsys PTH Immunoassay" and "Elecsys PTH STAT Immunoassay" devices, seeking to demonstrate substantial equivalence to a predicate device (Elecsys PTH Assay, K992680). The information mainly focuses on comparing the features and performance of the modified devices against the predicate, particularly in terms of assay duration, platforms, and analytical performance characteristics like precision.

1. Table of Acceptance Criteria and Reported Device Performance:

The document doesn't explicitly state "acceptance criteria" in a go/no-go format for external validation. Instead, it presents a comparison of the modified devices' performance characteristics against those of the predicate device (Elecsys PTH Assay, K992680), implying that performance similar to or improved over the predicate is acceptable. The detailed aspects compared are:

Study Details:

The provided text is a 510(k) summary for in vitro diagnostic (IVD) devices. IVD submissions of this nature primarily rely on analytical performance studies to demonstrate substantial equivalence to a predicate device, rather than the types of clinical or comparative effectiveness studies often associated with diagnostic imaging AI.

2. Sample Size Used for the Test Set and Data Provenance:

The document provides specific data points for precision studies, which serve as the "test set" for this type of analytical device. However, the exact total sample size (number of individual patient samples) for these precision studies is not explicitly stated. Instead, it reports Coefficient of Variation (CV) values at different mean PTH concentrations, which are typically derived from replicate measurements of control materials or pooled patient samples over several runs.

• Elecsys PTH (18 min appl.) Precision Study Data:
  • Within-run CV: 2.7% @ 26.7 pg/mL, 1.6% @ 52.5 pg/mL, 1.5% @ 261 pg/mL, 4.1% @ 20.2 pg/mL, 2.2% @ 58.0 pg/mL, 1.9% @ 676 pg/mL (Elecsys 2010/cobas e411)
  • Total CV: 6.5% @ 26.7 pg/mL, 3.9% @ 52.5 pg/mL, 3.0% @ 261 pg/mL, 6.2% @ 20.2 pg/mL, 4.1% @ 58.0 pg/mL, 2.6% @ 676 pg/mL (Elecsys 2010/cobas e411)
  • Within-run CV: 2.0% @ 21.9 pg/mL, 1.2% @ 35.0 pg/mL, 1.1% @ 123 pg/mL, 2.2% @ 72.7 pg/mL, 2.8% @ 236 pg/mL, 0.6% @ 1,092 pg/mL (E170/cobas e601)
  • Total CV: 3.4% @ 23.2 pg/mL, 2.5% @ 80.9 pg/mL, 2.8% @ 240 pg/mL, 1.7% @ 73.0 pg/mL, 1.6% @ 238 pg/mL, 1.6% @ 1,098 pg/mL (E170/cobas e601)
• Elecsys PTH STAT (9 min appl.) Precision Study Data:
  • Within-run CV: 5.4% @ 30.0 pg/mL, 4.0% @ 62.2 pg/mL, 4.0% @ 271 pg/mL, 5.8% @ 44.3 pg/mL, 3.4% @ 161 pg/mL, 3.9% @ 702 pg/mL (Elecsys 1010)
  • Total CV: 5.9% @ 30.0 pg/mL, 4.3% @ 62.2 pg/mL, 4.3% @ 271 pg/mL, 7.1% @ 44.3 pg/mL, 5.0% @ 161 pg/mL, 5.4% @ 702 pg/mL (Elecsys 1010)
  • Within-run CV: 2.1% @ 53.4 pg/mL, 1.7% @ 215 pg/mL, 1.7% @ 980 pg/mL, 1.6% @ 52.6 pg/mL, 2.0% @ 182 pg/mL, 1.8% @ 744 pg/mL (Elecsys 2010/cobas e411)
  • Total CV: 3.8% @ 53.4 pg/mL, 2.8% @ 215 pg/mL, 2.5% @ 980 pg/mL, 1.9% @ 52.6 pg/mL, 2.5% @ 182 pg/mL, 2.2% @ 744 pg/mL (Elecsys 2010/cobas e411)

The data provenance (country of origin, retrospective/prospective) is not specified in the provided text. For IVD devices, such studies are typically performed in a controlled laboratory setting.

3. Number of Experts Used to Establish the Ground Truth for the Test Set and the Qualifications of Those Experts:

This is not applicable to the type of device and study described. For an immunoassay, the "ground truth" for analytical performance studies is typically established by physical measurements and reference materials with known concentrations, or by comparison to a well-established reference method, not by expert consensus or interpretations in the way it applies to diagnostic imaging.

4. Adjudication Method for the Test Set:

Not applicable. As described above, the "test set" here refers to analytical performance data, not a set of cases requiring adjudication by human experts.

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 an IVD device for quantitative determination in serum/plasma, not a diagnostic imaging AI system that would involve human readers or MRMC studies.

6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) was done:

The device itself is a standalone analytical instrument (immunoassay) that provides quantitative results. Its performance, as detailed in the precision data, is "algorithm only" in the sense that it mechanically measures and processes a sample to produce a numerical result without human interpretation of raw data for diagnosis. The output (PTH concentration) is then used by a clinician for diagnosis, but the measurement itself is automated.

7. The Type of Ground Truth Used:

For this type of IVD, the "ground truth" for analytical performance tests would be established through a combination of:

• Reference Materials/Standards: Samples with known, certified concentrations of PTH.
• Comparison to a Validated Reference Method: The document states the methods were "standardized against a commercial PTH test (RIA)," implying that the RIA assay serves as a reference for establishing accuracy and traceability.

8. The Sample Size for the Training Set:

This concept of a "training set" is not directly applicable in the context of an immunoassay like the Elecsys PTH. These devices are based on established biochemical principles (sandwich immunoassay, electrochemiluminescence) and calibrated using reference materials. There isn't a "machine learning algorithm" in the typical sense that requires a large dataset for training. The instrument's internal "algorithm" refers to its pre-programmed measurement and calculation logic, which is developed based on the assay's chemical characteristics and repeatedly verified with controls and calibrators.

9. How the Ground Truth for the Training Set Was Established:

As explained above, there isn't a "training set" in the machine learning sense. The "ground truth" relevant to the device's operational parameters and calibration would be established through:

• Calibrator materials: These are supplied with known values. The "calibration curve" is generated by the instrument using these calibrators and a master curve provided with the reagent bar code. These calibrator values are derived from rigorously tested and traceable reference materials.
• Quality control materials: Used to continually verify the accuracy and precision of the instrument.

Ask a specific question about this device