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ExSpiron 2Xi is indicated for use by healthcare professionals in healthcare facilities, such as post-operative care and critical care units, to monitor breathing in patients at least 1 - year of age.

ExSpiron 2Xi is a non-invasive monitor that graphically displays lung volume against time and reports an approximate value of:

• Minute Ventilation (MV)

• Tidal volume (TV)

• Respiratory Rate (RR)

ExSpiron 2Xi measurements are used as an adjunct to other clinical information.

The ExSpiron 2Xi Respiratory Monitor System consists of:
Monitor: The Monitor contains a bioimpedance measurement system and a tablet PC housed within a single enclosure.
Bioimpedance measurement system: The Monitor incorporates a stabilized high frequency current generator and an adaptive circuit that conditions the resulting voltage signal and converts it to digital form. Firmware within the Monitor performs signal acquisition and relays data to the tablet PC.
Computer: A tablet PC performs signal processing and calibration and runs the graphical user interface (GUI). The PC takes user input from a touch screen through a virtual keyboard and mouse. The GUI is used for recording patient data and displaying the respiratory trace as well as scalar values and trends for minute ventilation, tidal volume, and respiratory rate.
Patient Cables and Electrode Padsets that are also included in the system but were cleared in previous 510(k)s: K130170, K162131, K173181
ExSpiron Patient Cable: A reusable cable that connects the ExSpiron 2Xi Monitor to the Electrode PadSet.
Single patient use ExSpiron Electrode PadSet: A Single-Patient Use Electrode PadSet is placed on the skin of the patient's torso. It delivers current to, and records impedance measurements from, the skin.

The provided document describes the ExSpiron 2Xi Respiratory Monitor System, focusing on its substantial equivalence to a predicate device (ExSpiron 1Xi).

1. Acceptance Criteria and Reported Device Performance

The acceptance criteria for the ExSpiron 2Xi are based on demonstrating substantial equivalence to its predicate (ExSpiron 1Xi). The key performance metric highlighted is Bench Accuracy for Minute Ventilation (MV), Tidal Volume (TV), and Respiratory Rate (RR), which serves as a surrogate for demonstrating equivalent performance.

The document states, "The accuracy of the proposed device is substantially equivalent to the predicate." This implies that the ExSpiron 2Xi's performance falling within a comparable range to the predicate's established performance fulfills the accuracy acceptance criterion.

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

The document does not specify a sample size for a particular "test set" in the context of clinical data for accuracy. Instead, it refers to "Bench Accuracy" testing. This suggests the primary testing for equivalence was done in a controlled, non-human, benchtop environment, rather than a clinical dataset of patients.

The data provenance is not explicitly stated in terms of country of origin or whether it was retrospective or prospective, as the clinical testing was deemed "not required" for this Special 510(k). The "large historical cohort" mentioned for algorithm training is not further detailed.

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

This information is not provided as the primary performance evaluation relied on "Bench Accuracy" testing, not clinical studies requiring expert ground truth for medical imaging/diagnoses.

4. Adjudication Method for the Test Set

This information is not applicable as the evaluation did not involve human readers interpreting a test set requiring adjudication.

5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study

An MRMC study was not conducted for this submission. The submission is a "Special 510(k)" which typically relies on design control changes and verification/validation testing to demonstrate substantial equivalence, rather than new clinical trials or comparative effectiveness studies with human readers. The document explicitly states, "Clinical testing was not required."

6. Standalone (i.e., algorithm only without human-in-the-loop performance) Study

The accuracy values provided for MV, TV, and RR are implied to be standalone performance metrics of the device itself, as they are derived from "Bench Accuracy" testing. There is no mention of human interaction influencing these reported accuracy percentages in the context of the device's output.

7. Type of Ground Truth Used

For the "Bench Accuracy" testing, the ground truth would likely be established through controlled measurements using calibrated testing equipment or simulated physiological models, where the true values of Minute Ventilation, Tidal Volume, and Respiratory Rate are known or precisely controlled. The document does not specify the exact nature of this "ground truth" for bench accuracy, but it would not be expert consensus, pathology, or outcomes data in this context.

8. Sample Size for the Training Set

The document states that the software algorithm was trained with "a dataset containing respiratory data from a large historical cohort." A specific sample size for this training cohort is not provided.

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

The document mentions that the algorithm uses a "proprietary, non-linear, regressive model trained with a dataset containing respiratory data from a large historical cohort." It does not explicitly state how the ground truth for this training data was established. It can be inferred that for the "respiratory data," ground truth would likely involve highly accurate reference measurements from other established monitoring methods (e.g., spirometry, capnography, or other gold standard methods) when the historical data was collected. However, this is conjecture based on typical medical device development, and not explicitly stated in the document.

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ExSpiron 1Xi is indicated for use by healthcare professionals in healthcare facilities, such as post-operative care and critical care units, to monitor breathing in patients at least one year of age.

ExSpiron 1Xi is a non-invasive monitor that graphically displays lung volume against time and reports an approximate value of:

• Minute Ventilation (MV)
• Tidal volume (TV)
• Respiratory rate (RR)
  ExSpiron 1Xi measurements are used as an adjunct to other clinical information.

The ExSpiron 1Xi is a noninvasive respiratory monitoring system that graphically displays lung volume against time and reports Minute Ventilation, Tidal Volume and Respiratory Rate.

The ExSpiron 1Xi system consists of:
• Monitor:
The Monitor contains a bioimpedance measurement system and a tablet PC housed within a single enclosure.
o Bioimpedance measurement system: The Monitor incorporates a stabilized high frequency current generator and an adaptive circuit that conditions the resulting voltage signal and converts it to digital form. Firmware within the Monitor performs signal acquisition and relays data to the tablet PC.

o Computer: A tablet PC performs signal processing and calibration, and runs the graphical user interface (GUI). The PC takes user input from a touch screen through a virtual keyboard and mouse. The GUI is used for recording patient data and displaying the respiratory trace as well as scalar values and trends for minute ventilation, tidal volume, and respiratory rate.

There are no hardware changes included in this submission.

Single-Patient Use ExSpiron Electrode PadSet:
• A Single-Patient Use Electrode PadSet is placed on the skin of the patient's torso. It delivers current to, and records impedance measurements from, the skin. The Electrode PadSet for the ExSpiron 1Xi is identical to that cleared for the Predicate device.

The acceptance criteria and study proving the device meets them are summarized below:

1. Table of Acceptance Criteria and Reported Device Performance:

Note: The document states that the equivalence tests rejected the null hypothesis that the ExSpiron 1Xi and NM3 have different mean values and concluded with 90% power that the measurements of MV, TV, and RR from the ExSpiron 1Xi and NM3 are equivalent within +/-10%. This indicates that the device met the acceptance criteria despite the accuracy error values being slightly outside the 10% for MV and TV in the table. The "accuracy error" values seem to represent the deviation, while the "equivalence tests" are the primary mechanism for meeting the criteria.

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

• Sample Size: 72 pediatric patients.
• Data Provenance: Prospective observational study conducted at Children's Hospital of Boston, USA.

3. Number of Experts and Qualifications for Ground Truth:

• The study utilized continuous respiratory data collected simultaneously from the ExSpiron 1Xi and a monitoring spirometer (Philips NM3, referred to as the reference device) placed in the respiratory circuit. The NM3 itself essentially served as the "expert" ground truth (or established reference) in this comparative study.
• No human experts were explicitly mentioned as establishing a separate ground truth for the test set; the NM3 measurements were the reference.
• The qualifications of the individuals operating the devices or interpreting the NM3 data are not specified, beyond general "healthcare professionals."

4. Adjudication Method:

• No explicit adjudication method (like 2+1, 3+1) was mentioned. The study directly compared measurements from the ExSpiron 1Xi to the reference device (NM3).

5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study:

• A MRMC comparative effectiveness study was not conducted in the context of human readers improving with or without AI assistance. This study was focused on the standalone performance of the ExSpiron 1Xi against a reference device, not on assisting human readers.

6. Standalone (Algorithm Only) Performance:

• Yes, a standalone study was performed. The clinical performance testing described is a standalone evaluation of the ExSpiron 1Xi's ability to measure MV, TV, and RR compared to a recognized reference device (Philips NM3) without a human-in-the-loop component.

7. Type of Ground Truth Used:

• The ground truth used was a reference device comparison. Specifically, the measurements from the Philips NM3 Respiratory Profile Monitor, a monitoring spirometer placed in the respiratory circuit, served as the reference standard for MV, TV, and RR.

8. Sample Size for the Training Set:

• The device's algorithm uses a "proprietary, non-linear, regressive model trained with a dataset containing respiratory data from a large historical cohort."
• The exact sample size for the training set is not provided in the document, but it is described as a "large historical cohort."

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

• The document states that the software algorithm calculates respiratory parameters using a model "trained with a dataset containing respiratory data from a large historical cohort."
• It does not explicitly detail how the ground truth for this historical training dataset was established. However, given the context of a medical device measuring physiological parameters, it's highly probable that this training data would have been collected using established, accurate measurement methods, likely similar to (or including) reference spirometry or other validated respiratory monitoring techniques.

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ExSpiron 1Xi is indicated for use by healthcare professionals in healthcare facilities, such as post-operative care and critical care units, to monitor breathing in adult (at least 21 years old) patients.

ExSpiron 1Xi is a non-invasive monitor that graphically displays lung volume against time and reports an approximate value of:

• Minute Ventilation (MV)

• Tidal volume (TV)

• Respiratory rate (RR)

ExSpiron 1Xi measurements are used as an adjunct to other clinical information.

The ExSpiron 1Xi is a noninvasive respiratory monitoring system that graphically displays lung volume against time and reports Minute Ventilation, Tidal Volume and Respiratory Rate.

The ExSpiron 1Xi system consists of:
Monitor:
The Monitor contains a bioimpedance measurement system and a tablet PC housed within a single enclosure.
Bioimpedance measurement system: The Monitor incorporates a stabilized high frequency current generator and an adaptive circuit that conditions the resulting voltage signal and converts it to digital form. Firmware within the Monitor performs signal acquisition and relays data to the tablet PC. Computer: A tablet PC performs signal processing and calibration, and runs the graphical user interface (GUI). The PC takes user input from a touch screen through a virtual keyboard and mouse. The GUI is used for recording patient data and displaying the respiratory trace as well as scalar values and trends for minute ventilation, tidal volume, and respiratory rate.
A Single-Patient Use Electrode PadSet is placed on the skin of the patient's torso. It delivers current to, and records impedance measurements from, the skin. The Electrode PadSet for the ExSpiron 1Xi is identical to that cleared for the Predicate device.

Acceptance Criteria and Device Performance for ExSpiron™ 1Xi

1. Table of Acceptance Criteria and Reported Device Performance

The provided document compares the proposed device (ExSpiron 1Xi) to a predicate device (ExSpiron™ 1Xi, K130170). The comparison focuses on various characteristics, including accuracy. While explicit "acceptance criteria" for accuracy are not stated as numerical thresholds, the document presents the accuracy results of the proposed device. The implied acceptance is that the proposed device performs at least as well as, or better than, the predicate device.

The document notes that the "algorithm was refined for the ExSpiron 1Xi using thousands of additional data points collected over the last 3 years in a wide variety of patient populations," leading to "more accurate respiratory volumes than the predicate." However, the accuracy percentages show a slight decrease in accuracy (higher percentage value) for MV and TV compared to the predicate in this summary document. This might be due to presenting overall clinical study results for the proposed device, while the predicate's numbers might be from a specific lab setting or a different calculation method for its initial clearance. The conclusion explicitly states the proposed device "is as safe and as effective as the predicate."

2. Sample Size for the Test Set and Data Provenance

• Sample Size: 20 subjects
  • Age range: 22-80
  • BMI range: 19-42
  • Gender: 9 female, 11 male
• Data Provenance:
  • Country of Origin: Waltham, MA, USA (clinical study conducted there)
  • Retrospective or Prospective: Prospective. The study was conducted specifically to compare simultaneous measurements from the ExSpiron 1Xi and the predicate device.

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

The document does not explicitly state the number of experts used to establish the ground truth for this clinical study, nor does it specify their qualifications. The study focused on comparing the performance of the proposed device against a predicate device through simultaneous measurements. This implies the predicate device's measurements or another recognized standard served as the comparative reference, rather than a separate "ground truth" established by experts for each breath.

4. Adjudication Method for the Test Set

The document does not describe an adjudication method for the test set. It states that simultaneous measurements were taken from both the proposed device and the predicate device, implying a direct comparison rather than a need for expert adjudication of independent measurements.

5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study

No, a Multi-Reader Multi-Case (MRMC) comparative effectiveness study was not done. The study described is a clinical study comparing simultaneous measurements of the proposed device and a predicate device on patients, not a study evaluating human reader performance with and without AI assistance.

6. Standalone Performance Study (Algorithm Only Without Human-in-the-Loop Performance)

Yes, a standalone performance aspect is implied. The "Accuracy" section of the comparison table and the clinical study results (Bias, Precision, Accuracy) directly assess the performance of the device's algorithms in measuring respiratory parameters (MV, TV, RR) without explicitly mentioning human intervention in the real-time measurement process. The device provides "approximate values" of these parameters.

7. Type of Ground Truth Used

The ground truth for the clinical study was established by simultaneous measurements from a legally marketed predicate device (ExSpiron™ 1Xi, K130170). The study aimed to show equivalence or improvement compared to an already cleared device.

8. Sample Size for the Training Set

• The predicate device's algorithm was "trained with a dataset containing respiratory data from a large historical cohort."
• The proposed device's algorithm was "refined for the ExSpiron 1Xi using thousands of additional data points collected over the last 3 years in a wide variety of patient populations." The exact numerical sample size ("thousands") is not specified beyond this qualitative description.

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

The document does not explicitly detail how the ground truth for the "large historical cohort" or the "thousands of additional data points" used for algorithm training/refinement was established. However, given the nature of a spirometer, it is highly probable that the ground truth for training data would have been established using:

• Reference Spirometry: Directly measured, highly accurate respiratory volumes and rates from calibrated gold-standard spirometry equipment.
• Other established physiological measurement techniques that provide accurate respiratory parameters.

The purpose of the training data is to allow the device's proprietary, non-linear, regressive model to accurately calculate respiratory parameters "without patient-specific calibration" for the proposed device.

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ExSpiron 1xi is indicated for use by healthcare professionals in healthcare facilities, such as post-operative care and critical care units, to monitor breathing in adult (at least 21 years old) patients.
ExSpiron 1xi is a non-invasive system that graphically displays lung volume against time and reports an approximate value of:
Tidal volume,
Respiratory rate, and
Minute ventilation
ExSpiron 1xi measurements are used as an adjunct to other clinical information sources.

The ExSpiron 1xi system consists of:
Bioimpedance measurement system: A stabilized high frequency current generator is connected to two outer electrodes. The inner four electrodes are connected to an adaptive circuit that conditions the resulting voltage signal and converts it to digital form. Firmware performs signal acquisition and relays data to the panel PC.
Computer: A Windows 7 PC performs signal processing and calibration, and runs the graphical user interface (GUI). The PC takes user input from a touch screen. The GUI is used for recording patient data and displaying the respiratory trace as well as scalar values and trends for minute volume, tidal volume, and respiratory rate.
Single Patient Use ExSpiron™ 1xi Electrode PadSet: An electrode assembly containing six electrodes to be placed on the torso. It delivers current and records impedance measurements. The electrode PadSet is also used to perform subsystem checks prior to patient measurements.

The ExSpiron™ 1xi respiratory monitor is indicated for use by healthcare professionals in healthcare facilities to monitor breathing in adult (at least 21 years old) patients. It is a non-invasive system that graphically displays lung volume against time and reports approximate values for Tidal Volume, Respiratory Rate, and Minute Ventilation. The measurements are used as an adjunct to other clinical information sources.

The provided documentation does not contain a table of acceptance criteria or reported device performance for this specific 510(k) submission (K130170). The submission is a Special 510(k) where the manufacturer states that "No clinical testing was performed for this 510(k). The measurement algorithm and software are unchanged from the predicate. Measurement performance statistics were determined by clinical trials reported in the predicate 510(k), K120087." This means that the device's performance relies on the data submitted for its predecessor, the ExSpiron Respiratory Monitor (K120087).

However, based on the information provided for K130170:

1. Table of Acceptance Criteria and Reported Device Performance:

As stated above, no specific acceptance criteria or reported performance for the ExSpiron™ 1xi is provided in this document as it references the predicate device. For the predicate device, K120087, the performance statistics would have been determined through clinical trials. Without access to K120087, these specific details cannot be provided here.

The document states that changes for K130170 were related to:

• Software Verification & Validation
• Safety Testing - IEC 60601-1 2nd Edition
• Electromagnetic Compatibility - IEC 60601-1-2
• ExSpiron 1Xi System Test Plan
• Patient Cable Design Verification (AAMI / ANSI EC53:1995/(R) 2008)
• Electrode PadSet Design Verification (AAMI / ANSI EC12:2000/(R)2010, AAMI / ANSI EC53:1995/(R) 2008)
• Electrode - Biocompatibility - ANSI/AAMI/ISO 10993-1

All performance testing for these modifications was reported as successful, raising no new safety or efficacy concerns and demonstrating substantial equivalence to the predicate device.

2. Sample Size for Test Set and Data Provenance:

• Sample Size for Test Set: Not applicable for this specific 510(k) (K130170) as no new clinical testing was performed. The measurement performance statistics were determined by clinical trials reported in the predicate 510(k), K120087.
• Data Provenance: Not applicable for this specific 510(k). For the predicate device (K120087), this information would be detailed in its submission. It's likely that the data would be prospective, given the nature of clinical trials for device performance. Country of origin not specified in the current document.

3. Number of Experts and Qualifications for Ground Truth - Test Set:

• Not applicable for this specific 510(k) (K130170) as no new clinical testing was performed. The ground truth for the predicate device's clinical trials (K120087) would have been established through a reference standard method, but the number and qualifications of experts are not described in this document.

4. Adjudication Method for the Test Set:

• Not applicable for this specific 510(k) (K130170) as no new clinical testing was performed.

5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study:

• No MRMC comparative effectiveness study was done for this specific 510(k) (K130170). The device is a monitor that reports values, not an AI for interpretation requiring human readers.

6. Standalone (Algorithm Only) Performance Study:

• Yes, implicitly. The statement that "The measurement algorithm and software are unchanged from the predicate" implies that the core algorithm's performance was evaluated in a standalone manner during the clinical trials for the predicate device (K120087). This 510(k) (K130170) focuses on modifications to hardware components and software updates that do not alter the fundamental measurement algorithm.

7. Type of Ground Truth Used:

• For the performance statistics referenced from the predicate K120087, the ground truth for respiratory measurements (Tidal Volume, Respiratory Rate, Minute Ventilation) would typically be established using a gold standard reference measurement system (e.g., highly accurate spirometry, capnography, or volumetric respirators) rather than expert consensus on images or pathology. The document does not specify the exact ground truth method used in the predicate study.

8. Sample Size for the Training Set:

• Not applicable for this 510(k) (K130170). The clinical trials for the predicate device (K120087) would have involved a patient sample. The document does not provide this information.

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

• Not applicable for this 510(k) (K130170). For the predicate device's clinical trials, the ground truth would have been established using a gold standard reference measurement system, as mentioned in point 7.

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ExSpiron is indicated for use by healthcare professionals in healthcare facilities, such as post-operative care and critical care units, to monitor breathing in adult (at least 21 years of age) patients.

ExSpiron is a non-invasive system that graphically displays lung volume against time and reports an approximate value of:

• Tidal volume, .
• . Respiratory rate, and
• Minute ventilation. ●

ExSpiron measurements are used as an adjunct to other clinical information sources.

The ExSpiron™ consists of:
Bioimpedance measurement system: A stabilized high frequency current generator is connected to two outer electrodes. The inner four electrodes are connected to an adaptive circuit that conditions the resulting voltage signal and converts it to digital form. Firmware performs signal acquisition and relays data to the panel PC.
Panel PC: A Windows 7 PC performs signal processing and calibration, and runs the graphical user interface (GUI). The PC takes user input from a touch screen through a virtual keyboard and mouse. The GUI is used for recording patient data and displaying the respiratory trace as well as scalar values and trends for minute volume, tidal volume, and respiratory rate.
Single Patient Use ExSpiron™ Electrode Lead Set: An electrode lead set containing six electrodes to be placed on the torso. It delivers current and records impedance measurements. The electrode lead set is also used to perform subsystem checks prior to patient measurements.

The provided 510(k) summary for the ExSpiron™ device includes information about its acceptance criteria and the study performed to demonstrate its performance.

Here's a breakdown of the requested information:

1. Table of Acceptance Criteria and Reported Device Performance

The acceptance criteria are implied by the comparison to the predicate device and the calculation of bias and accuracy. The specific pass/fail thresholds for these metrics are not explicitly stated as "acceptance criteria" but are presented as the device's performance against a reference.

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

• Sample Size for ExSpiron-Wright study: 20 subjects
• Sample Size for Wright-Morgan study: 20 subjects (a different set of subjects)
• Data Provenance: The document does not explicitly state the country of origin, but it is a 510(k) submission to the FDA, suggesting the study was conducted to support US market approval. The study design (clinical comparison) implies prospective data collection for the purpose of the submission.

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

Not applicable. This device is a measurement device, and its performance is compared directly against existing medical devices (Wright spirometer and Morgan SpiroAir LT diagnostic spirometer), which are considered the reference or "ground truth" for these measurements. There is no mention of human experts establishing ground truth for individual measurements.

4. Adjudication Method for the Test Set

Not applicable. As noted above, the ground truth was established by direct measurement from predicate devices, not by expert adjudication.

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. The ExSpiron™ is a medical device for monitoring physiological parameters (tidal volume, minute ventilation, respiratory rate), not an AI-powered diagnostic tool for interpretation by human readers. Therefore, an MRMC study or AI assistance effect size is not relevant to this submission.

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

Yes, the clinical performance testing describes a standalone assessment of the ExSpiron™ device. Its measurements were compared directly and simultaneously with those from the predicate devices (Wright spirometer and, indirectly, Morgan diagnostic spirometer). The output of the ExSpiron (tidal volume, minute ventilation, respiratory rate) is generated solely by the device based on its bioimpedance measurements and internal algorithms, without human intervention in the measurement process itself.

7. The Type of Ground Truth Used

The ground truth used was measurement from predicate medical devices:

• Wright spirometer: for tidal volume, minute ventilation, and respiratory rate. Respiratory rate was calculated using a stopwatch in conjunction with the Wright spirometer.
• Morgan SpiroAir LT diagnostic spirometer: for tidal volume and minute ventilation in a separate comparative study with the Wright spirometer. This allowed for an indirect comparison between the ExSpiron and the Morgan device.

8. The Sample Size for the Training Set

The document does not explicitly mention a "training set" in the context of machine learning or AI. The ExSpiron™ uses a "Bioimpedance measurement system" with "Firmware performs signal acquisition and relays data to the panel PC. Panel PC: A Windows 7 PC performs signal processing and calibration." It also states "the ExSpiron was calibrated to the individual" in the clinical study. This suggests a traditional signal processing approach with individual calibration, rather than a large dataset-based machine learning training paradigm. Therefore, a specific "training set sample size" as understood in AI development is not provided or likely applicable in the conventional sense for this device.

9. How the Ground Truth for the Training Set was Established

Similar to the point above, a traditional "training set ground truth" is not explicitly described. Instead, the device undergoes individual calibration for each subject against known physiological signals or reference measurements at the time of use. The clinical study details that "electrodes were applied, the ExSpiron was calibrated to the individual, and each subject performed ten 60-second breathing tests." This initial calibration likely establishes the individual's baseline and correlation for the bioimpedance measurements before subsequent monitoring.

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