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The NOVA is an electrophysiological device that generates photic stimuli, and records, processes and analyzes the resultant visual evoked potential (VEP) signals to provide information about the visual system structural and neural abnormalities.

Checkerboard, Horizontal grating, Vertical grating, Sinusoidal grating, Flash, monochromatic pattern onset or color pattern onset Contrast Photic stimuli are presented to the patient on a calibrated computer monitor at various numbers of elements in separately stimulated fields. The fields are varied in spatial size over a number of cycles. The fields are also phase reversed at different temporal frequencies. The signals are analyzed by the software algorithm for spatial/temporal filtering and artifact rejection. Data may be presented in numerical and graphical form. The device also utilizes attention grabbing features specifically for children or non attentive adults. In particular, a picture is presented prior to the onset of the VEP pattern stimulus. During the picture presentation no data is collected. Age appropriate music is also available to patient as well. The music is only intended as an attention facilitator. From a hardware standpoint the NOVA system is identical to that of the Enfant, ® which was cleared under K043491. The only difference between the two devices is the software.

The provided text describes the Diopsys™ NOVA VEP Vision Testing System, focusing on its substantial equivalence to predicate devices rather than proving its performance against specific acceptance criteria through a clinical study. The performance data section refers to verification and validation activities, which are internal engineering tests, not clinical efficacy studies.

Therefore, much of the requested information regarding acceptance criteria, sample size for test sets, data provenance, expert ground truth, adjudication methods, MRMC studies, standalone performance, and training set details cannot be extracted from the given document.

However, I can provide what is available:

1. Table of Acceptance Criteria and Reported Device Performance:

The document does not explicitly state "acceptance criteria" for clinical performance. Instead, it lists various verification and validation activities for the software and hardware. The "reported device performance" in this context refers to the successful completion of these internal tests.

2. Sample size used for the test set and the data provenance:

• The document describes verification and validation activities, which typically involve internal testing of the device and software, not a clinical "test set" with a specified sample size of patient data.
• Data Provenance: Not applicable for these internal engineering tests. No information about country of origin or retrospective/prospective nature of patient data is provided.

3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts:

• Not applicable. The performance data pertains to internal engineering verification and validation, not clinical ground truth established by experts.

4. Adjudication method (e.g. 2+1, 3+1, none) for the test set:

• Not applicable. No clinical test set requiring expert adjudication is mentioned.

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:

• No MRMC or comparative effectiveness study is mentioned. The device is a diagnostic tool (VEP system), and the submission focuses on its substantial equivalence to predicate VEP systems, not its impact on human reader performance.

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

• The "Performance Data" section describes software verification and validation, including "Comparison of EEG Response Verifies VEP recording compared to known recording." This, along with "Signal Test Procedure VEP recordings are displayed as expected," suggests standalone performance of the algorithm in processing and displaying VEP data. However, it's not a clinical standalone performance study in the context of diagnostic accuracy against a ground truth. It's more about the algorithm functioning as intended with known inputs.

7. The type of ground truth used (expert consensus, pathology, outcomes data, etc):

• For the verification and validation (V&V) activities described, the "ground truth" is primarily based on known specifications, expected behaviors, and known recordings. For example, "Verifies VEP stimulus parameters meet specification" and "Verifies VEP recording compared to known recording." This is not clinical ground truth.

8. The sample size for the training set:

• The document does not mention any training data or training set for the device's software/algorithms. This is common for VEP systems, which often use established signal processing techniques rather than machine learning models requiring extensive training data.

9. How the ground truth for the training set was established:

• Not applicable, as no training set is mentioned.

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The Enfant is a non-invasive medical device to screen, without dilation or sedation, for visual disorders in infants and pre-school children. The system uses Visual Evoked potentials to provide information about the visual pathway function and about optical or neural abnormalities related to vision.

Horizontal Contrast Photopic stimuli are presented to the patient on a computer monitor at various numbers of elements in separately stimulated fields. The fields are varied in spatial size over a number of cycles. The signals are analyzed by the software using algorithms for spatial filtering and artifact rejection. Data may be presented in number form and on a graph. The device also adds some attention features specifically for children. In particular, a cartoon is presented prior to the VEP pattern. During the Cartoon presentation no data is collected. Age appropriate music is also presented to patient as well. The music is only intended as an attention facilitator.

The Enfant™ System is a non-invasive medical device designed to screen for visual disorders in infants and pre-school children without requiring dilation or sedation. It uses Visual Evoked Potentials (VEP) to assess visual pathway function and identify optical or neural abnormalities related to vision.

Here's an analysis of its acceptance criteria and the supporting study:

1. Acceptance Criteria and Reported Device Performance

The provided document does not explicitly state pre-defined acceptance criteria in terms of specific performance metrics (like minimum sensitivity, specificity, etc.) for marketing authorization. However, the clinical performance study itself establishes the device's measured effectiveness, which implicitly served as the basis for substantial equivalence with predicate devices.

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

• Sample Size for Test Set: 122 children
• Ages: 6 months to 5 years
• Data Provenance: The study was an investigational new drug (IND) approved study conducted in children. The specific country of origin is not explicitly stated, but Diopsys, Inc. is located in Pine Brook, NJ, USA, and the FDA letter indicates a US regulatory context. The study design implies prospective data collection as it involved intentionally testing children with the Enfant™ system and comparing results masked to a gold standard.

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

• Number of Experts: Not explicitly stated as a number of individual experts. The "results of standard ophthalmlogic examination" was used as the reference. This implies multiple ophthalmologists were involved in the standard clinical diagnoses.
• Qualifications of Experts: The ground truth was established by "standard ophthalmologic examination." For verbal patients, clinical amblyopia was defined by an interocular difference of two or more lines in best-corrected visual acuity. For preverbal children, ground truth was based on the clinician's decision to treat with occlusion or atropine penalization, or the presence of any other typical eye pathology. This indicates that board-certified ophthalmologists were the experts, providing clinical diagnoses typical of their practice.

4. Adjudication Method for the Test Set

The study describes "comparing test results in masked fashion to results of standard ophthalmologic examination." This implies that the Enfant™ system's results were interpreted independently (masked) from the ophthalmologic examination results. A "statistical program" then analyzed VEP differences and assigned a "pass" or "fail" for each child. While not explicitly specifying an adjudication method for conflicting results between experts, the structure suggests the "standard ophthalmologic examination" served as the definitive ground truth against which the device's output was compared. No specific 2+1 or 3+1 type of expert adjudication is mentioned for establishing the ground truth itself; rather, the clinical diagnosis by an ophthalmologist was the gold standard.

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

No, a multi-reader, multi-case (MRMC) comparative effectiveness study was not performed as described in this document. The study focused on the standalone performance of the Enfant™ system compared to clinical diagnosis, rather than comparing human readers with and without AI assistance.

6. Standalone Performance Study

Yes, a standalone performance study was performed. The study aimed to evaluate the Enfant™ system's ability to screen for visual disorders by comparing its "pass" or "fail" results directly against the gold standard of "standard ophthalmologic examination." The reported sensitivity, specificity, PPV, and NPV are all measures of this standalone algorithm's performance.

7. Type of Ground Truth Used

The type of ground truth used was expert clinical diagnosis/examination (ophthalmology).

• For verbal patients: Clinical amblyopia was defined as an interocular difference of two or more lines in best-corrected visual acuity.
• For preverbal children: Clinical amblyopia was defined by the clinician's decision to treat with occlusion or atropine penalization, or the presence of any other typical eye pathology.

8. Sample Size for the Training Set

The document does not provide information regarding a distinct training set sample size. The study described is a clinical validation study, likely assessing the performance of a system that was developed and potentially trained on other data not detailed here.

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

As no information is provided about a specific training set or its sample size, an explanation of how its ground truth was established cannot be given based on the provided text.

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