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The QCT Pro Asynchronous Calibration Module is intended to provide an alternative method for calibrating QCT data sets that are intended for analysis with QCT Pro Spine and Hip application modules. Installation of the QCT Pro Asynchronous Calibration Module does not alter the clinical indications for use of the QCT Pro Spine and Hip application modules. It does, however, provide an additional means of obtaining calibration data that does not require the simultaneous scanning of a patient with a CT calibration standard as is required when using the QCT Pro Spine and Hip application modules without the installation of the QCT Pro Asynchronous Calibration Module. Thus the QCT Pro Asynchronous Calibration Module facilitates: (1) retrospective assessment of bone density from CT scans acquired for other purposes, (2) assessment of bone density in conjunction with another medically appropriate procedure involving CT scans of the anatomical regions where estimating bone density is prescribed, and (3) assessment of bone density without a phantom as an independent measurement procedure.

The QCT Pro Asynchronous Calibration Module is intended to extend the capabilities of QCT Pro bone mineral densitometer products (K894854. K002113. K030330) currently marketed by Mindways to the measurement of bone mineral content (BMC) and bone mineral density (BMD) from patient-specific CT images acquired without the simultaneous use of a CT calibration phantom. The QCT Pro bone mineral densitometer products distributed with or supplemented with the QCT Pro Asynchronous Calibration Module will be marketed under the name QCT Pro CliniQCT or more simply CliniQCT. Mineral calibration with the asynchronous calibration method is obtained from phantom measurements acquired on the same CT scanner, operated in a substantially similar mode used to acquire a patient CT scan. The phantom measurements used for calibration purposes may be acquired before or after a patient CT scan to which they are to be applied. The asynchronous calibration mode facilitates: (1) retrospective assessment of bone density from CT scans acquired for other purposes, (2) assessment of bone density in conjunction with another medically appropriate procedure involving CT scans of the anatomical regions where estimating bone density is prescribed, and (3) assessment of bone density without a phantom as an independent measurement procedure. Retrospective bone density analysis provides bone density information without exposing a patient to additional ionizing radiation while combining CT studies results in an overall reduction in patient exposure to ionizing radiation relative to the expected radiation dose associated with performing the studies separately.

Here's an analysis of the acceptance criteria and study detailed in the provided document, restructured to address your specific points:

The document describes the QCT Pro Asynchronous Calibration Module (marketed as CliniQCT), which provides an alternative calibration method for QCT data sets without requiring a simultaneous CT calibration phantom scan with the patient.

1. Table of Acceptance Criteria and Reported Device Performance

Note: The document states that the new device has "the same technological characteristics as its predicate QCT Pro devices" with the exception of the asynchronous calibration method, and that "BMD estimates derived with the asynchronous calibration method are suitable for comparison to the same reference data sets as are used with the QCT Pro predicate devices." This implies that the performance metrics (precision, accuracy) of CliniQCT are expected to be on par with the predicate devices.

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

The document states that the testing involved:

• Retrospective data analysis
• Phantom testing
• Prospective patient studies

However, specific sample sizes for the test set (number of images, patients, or phantoms) are not explicitly provided in the excerpt. The data provenance (e.g., country of origin, retrospective or prospective) is partially indicated by "retrospective data analysis" and "prospective patient studies," but further details (like country/institution) are missing.

3. Number of Experts Used to Establish Ground Truth and Their Qualifications

The document does not provide information regarding the number of experts used to establish ground truth or their qualifications. The device appears to be for quantitative measurements (BMC/BMD) rather than diagnostic image interpretation requiring expert consensus.

4. Adjudication Method for the Test Set

The document does not specify an adjudication method. Since the device provides quantitative measurements (BMC/BMD) rather than classification/diagnosis for which human readers would typically adjudicate, an adjudication method for a "test set" in the traditional sense of diagnostic image review is not applicable here. Performance is evaluated against objective reference standards and comparison to predicate devices.

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

An MRMC comparative effectiveness study was not conducted, or at least not described in this document. The device is a quantitative measurement tool (densitometer) and not designed for human-in-the-loop diagnostic image interpretation where AI assistance to human readers would be evaluated. The focus is on the accuracy and precision of the quantitative measurements produced by the device itself, compared to existing, validated methods.

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

Yes, the study primarily describes the standalone performance of the CliniQCT device. The "non-inferiority" and "unbiased" claims for precision and accuracy directly reflect the algorithm's performance in generating BMC and BMD values. It is a tool that provides quantitative data, and its performance evaluation is centered on the accuracy and reliability of these quantitative outputs.

7. The Type of Ground Truth Used

The ground truth used for evaluating the device appears to be:

• Calibration Reference Standard: For in vitro precision and accuracy, the device's output is compared against established calibration reference standards (e.g., aqueous K2HPO4 bone density standard).
• Predicate QCT Pro device outputs: For in vivo precision and similarity of BMC/BMD estimates, the device's performance is compared against the performance characteristics of its predicate QCT Pro devices, which are already legally marketed and established.

8. The Sample Size for the Training Set

The document does not specify a separate training set sample size. The testing described ("retrospective data analysis, phantom testing and prospective patient studies") appears to be for evaluating the device's performance (validation), not for initial model training data, as the device's underlying principles are based on Quantitative Computed Tomography (QCT) and existing predicate technology.

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

Since a separate "training set" is not explicitly mentioned for a machine learning model, the concept of ground truth establishment for a training set in that context is not directly applicable here. The device's calibration and underlying algorithms would be based on established QCT principles and phantom measurement protocols. The phrase "calibration data necessary for use with the QCT Pro Asynchronous Calibration Module is obtained from a standard QCT Pro QA phantom CT scan performed on the same CT scanner" suggests calibration is done using physical phantoms with known density values.

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The DXAVIEW™ Hip and Spine bone densitometry options are intended to estimate bone mineral content (BMC) and bone mineral density (BMD) in the proximal femur and spine. The BMD may be compared to DXA reference data. T-Scores and Z-Scores are calculated with respect to young normal and age matched reference data, and can be used by the physician in determining fracture risk.

The DXAVIEW™ Hip and Spine bone densitometry Options are intended to provide estimates of bone mineral density (BMD) and bone mineral content (BMC) in the proximal femur and spine. Young normal reference data taken from caucasian populations can be used to calculate T-Scores. Age matched normal reference data arc used to calculate Z-Scores. The BMD results, along with the T- and Z-Scores, can be used by physicians in their determination of fracture risk and therapy effectivencss.

The DXAView" Hip and Spine are software Options to the Image Analysis QCT-3D Plus product, which provides 3D projection measurements similar to conventional DXA. The product Options provide estimates of bone mineral content (BMC) and bone density (BMD) of the proximal femur and spine. BMC is expressed in grams and BMD in g/cm2 of calcium hydroxyapatite. DXAView™ uses phantom calibration by Quantitative Computed Tomography (QCT) on all compatible CT scanners. The computations are preformed on 3D CT volumetric image sets obtained with conventional CT protocols and radiation doses.

Here's a breakdown of the acceptance criteria and study information for the DXAView™ Hip and Spine device, based on the provided text:

1. Table of Acceptance Criteria and Reported Device Performance

Note: The document does not explicitly state numerical "acceptance criteria" but rather describes the "Summary of Clinical Performance Data" and "Conclusions" from the validation studies, which implicitly serve as the criteria for deemed substantial equivalence.

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

• Test Set Sample Size: The document refers to "Patient validation studies" and "Clinical studies comparing DXA and DXAVIEW™ for BMD of the hip." However, the exact numerical sample size for these clinical studies (test set) is not specified.
• Data Provenance: Not explicitly stated. It refers to "clinical comparison studies," but neither the country of origin nor whether the data was retrospective or prospective is mentioned.

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

• This information is not provided in the document. The studies focused on comparing the DXAView™ software to DXA results, implying DXA itself served as a reference, but no mention of human experts establishing ground truth for the test set is given.

4. Adjudication Method for the Test Set

• This information is not provided in the document.

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

• No, an MRMC comparative effectiveness study is not mentioned. The document focuses on comparing the algorithm's output (DXAVIEW™) to a reference standard (DXA), not on how human readers' performance might improve with or without AI assistance.

6. Standalone (Algorithm Only) Performance Study

• Yes, a standalone performance study was done. The "Clinical Performance Data" and "Conclusions" describe the performance of the DXAVIEW™ software directly (e.g., its precision, correlation with DXA), without mentioning a human-in-the-loop component. The device itself is described as "software Options to the Image Analysis QCT-3D Plus product."

7. Type of Ground Truth Used

• The ground truth used was comparison to a predicate device (DXA). The document states, "Clinical studies comparing DXA and DXAVIEW™ for BMD of the hip showed correlation coefficients R of 0.93-0.94." It also mentions the new device provides "estimates of bone mineral content (BMC) and bone mineral density (BMD) values similar to those obtained from the predicate DXA device." This implies DXA measurements served as the reference standard (ground truth) for the clinical validation.

8. Sample Size for the Training Set

• The document does not specify a separate training set sample size. It describes the validation studies. Since the device uses reference data (NHANES III) for T-Scores and Z-Scores, this reference data itself could be considered a form of "training" or foundational data, but its sample size is not stated in relation to the device's development.

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

• The document does not detail how a training set's ground truth was established, as it primarily focuses on the validation against DXA. It mentions that "NHANES III Standardized Reference Data are used to calculate T-Scores and Z-Scores." The ground truth for such standardized reference data like NHANES III would typically be established through large-scale, cross-sectional population studies using direct measurements (e.g., DXA) from a diverse cohort to establish population norms.

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