(242 days)
Prism is a neurofeedback software device intended for relaxation and stress reduction through the use of EEG biofeedback. The device is indicated as an adjunctive treatment of symptoms associated with posttraumatic stress disorder (PTSD), to be used under the direction of a healthcare professional, together with other pharmacological and/or non-pharmacological interventions.
Prism is a software as medical device, to be prescribed for treatment of patients with PTSD by clinicians as adjunct to standard of care. Prism is a software device running on a laptop that uses EEG signal input from an EEG device (g.Nautilos PRO (K171669)). Prism therapy consists of 15, 30-minute sessions and optional periodic refresher sessions. During a session, the patient is connected to 8 or more EEG channels and views an interactive audio/visual interface.
Acceptance Criteria and Device Performance Study for Prism Device
The Prism device is a neurofeedback software device intended for relaxation and stress reduction through the use of EEG biofeedback, specifically indicated as an adjunctive treatment for symptoms associated with Posttraumatic Stress Disorder (PTSD). The acceptance criteria for its effectiveness were defined by the primary performance measure of a prospective, single-arm, open-label, unblinded study.
The primary effectiveness hypothesis was that from baseline to the 3-month follow-up, at least 50% of study participants would experience a response to the treatment, defined as a 6-point reduction in the Clinician Administered PTSD Scale (CAPS-5) score from baseline.
1. Acceptance Criteria and Reported Device Performance
Table: Acceptance Criteria and Reported Device Performance
| Acceptance Criteria (Primary Endpoint) | Reported Device Performance (Efficacy Analysis Set) |
|---|---|
| At least 50% of study participants will experience a 6-point (or more) reduction in CAPS-5 score from baseline to the 3-month follow-up visit. | 66.67% of participants showed a ≥6-point reduction in CAPS-5 at 3 months follow-up. |
| Secondary Performance Measures (additional context, not primary acceptance criteria): |
- 54.55% of participants showed a ≥10-point reduction in CAPS-5 at 3 months follow-up.
- 50.00% of participants showed a ≥13-point reduction in CAPS-5 at 3 months follow-up. |
Safety Acceptance Criteria (Implicit):
The pre-specified safety goals of the study were met, indicating an acceptable safety profile. This would implicitly mean that the incidence and severity of adverse events were within acceptable clinical limits for the target population and device type.
2. Sample Size and Data Provenance
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Test Set (Clinical Study Participants):
- Screened: 101 subjects
- Full Analysis Dataset: 79 subjects
- Efficacy Analysis Set: 66 subjects (This is the primary sample size for evaluating the effectiveness against the acceptance criteria).
- Per-Protocol Analysis Set: 63 subjects
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Data Provenance: The study was a prospective, single-arm, open-label, unblinded study. It was conducted at 4 sites outside the United States (OUS) in Israel and one US site. This indicates a combination of Israeli and US data.
3. Number of Experts and Qualifications for Ground Truth
The document does not explicitly state the number of experts used to establish ground truth for the test set. However, it mentions:
- Diagnosis of PTSD: Established according to the DSM-5 criteria and CAPS-5.
- Clinician assessments: Performed and documented by the investigator or qualified and trained designee.
This implies that the ground truth for PTSD diagnosis and symptom severity (CAPS-5 scores) was established by licensed healthcare professionals (investigators or their designees) who were qualified to administer and interpret DSM-5 and CAPS-5. While specific qualifications (e.g., "radiologist with 10 years of experience") are not provided, "qualified and trained designee" suggests adherence to clinical standards for diagnostic assessment.
4. Adjudication Method for the Test Set
The document does not describe a formal adjudication method (like 2+1 or 3+1 consensus) for the initial PTSD diagnosis or CAPS-5 scoring. The assessments were performed by the "investigator or qualified and trained designee." This implies that the initial assessment by a single qualified professional served as the ground truth.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
There is no indication of a Multi-Reader Multi-Case (MRMC) comparative effectiveness study comparing human readers with and without AI assistance. The study described is a single-arm clinical study evaluating the device's adjunctive efficacy.
6. Standalone (Algorithm Only) Performance
The study evaluates the Prism software in conjunction with an EEG device (g.Nautilos PRO) as an adjunctive treatment for PTSD. Therefore, this is not a study of standalone algorithm performance without human-in-the-loop, as the device provides visual feedback to the patient to aid in learning to control EEG activity, and it is used under the direction of a healthcare professional.
7. Type of Ground Truth Used
The ground truth for effectiveness was based on:
- Clinical Assessments: Clinician Administered PTSD Scale (CAPS-5) scores. CAPS-5 is a structured interview administered by a trained clinician and is considered the gold standard for PTSD diagnosis and severity assessment.
- Self-Report Questionnaires: (Secondary measures, not primary ground truth for the acceptance criteria) PTSD Checklist for DSM-5 (PCL-5), Emotion Regulation Questionnaire (ERQ), Patient Health Questionnaire (PHQ-9), Clinical Global Impression (CGI).
8. Sample Size for the Training Set
The document does not provide information regarding the training set size or how the device's algorithms were trained. The provided text describes the clinical study for device validation, not the development or training phase of the software.
9. How Ground Truth for Training Set was Established
As information on the training set is not provided, the method for establishing its ground truth is also not described in this document.
§ 882.5050 Biofeedback device.
(a)
Identification. A biofeedback device is an instrument that provides a visual or auditory signal corresponding to the status of one or more of a patient's physiological parameters (e.g., brain alpha wave activity, muscle activity, skin temperature, etc.) so that the patient can control voluntarily these physiological parameters.(b)
Classification. Class II (special controls). The device is exempt from the premarket notification procedures in subpart E of part 807 of this chapter when it is a prescription battery powered device that is indicated for relaxation training and muscle reeducation and prescription use, subject to § 882.9.