(245 days)
The NET Device is a transcutaneous alternating current stimulator (ACS) that is intended to be used in patients experiencing opioid withdrawal in conjunction with standard symptomatic medications and other therapies for opioid withdrawal symptoms under the supervision of trained clinical personnel.
The NET Device is a non-invasive, battery-powered, portable, prescription device designed to provide bilateral, transcranial, transcutaneous, alternating current stimulation (tACS) to be used in patients experiencing opioid withdrawal under the supervision of trained clinical personnel. The system is comprised of one component (the NET Device), accessories (patient leads, electrodes, USB cable), and software (the clinician application). NET Devices, patient leads, and USB cables are reusable. No reprocessing, sterilization, maintenance, or recalibration is required. Electrodes are for single patient use only. The NET Device is used in professional healthcare facility environments (e.g., rehab centers and hospitals). If benefit is not established within 60 minutes of use, discontinue use and seek other methods of treatment.
The provided document is a 510(k) summary for the NET Device, which is a transcutaneous alternating current stimulator intended for patients experiencing opioid withdrawal. The study described focuses on demonstrating the substantial equivalence of the NET Device to its predicate device, the Sparrow Therapy System.
Here's an analysis of the acceptance criteria and the study that proves the device meets them:
1. A table of acceptance criteria and the reported device performance
The document doesn't explicitly state "acceptance criteria" for performance in a tabular format. Instead, it defines a clinically meaningful decline in COWS (Clinical Opiate Withdrawal Scale) score as ≥15% reduction from baseline to 1-hour after the start of active NET stimulation, and then reports the device's performance against this benchmark. Safety is assessed by the absence of device-related adverse events and comparison of risk profiles to the predicate device.
| Acceptance Criterion (Implicit) | Reported Device Performance (NET Device) |
|---|---|
| Effectiveness: Achieve a statistically significant clinically meaningful decline in COWS total score from baseline to 1-hour. | Achieved: The mean COWS total score in the active NET group decreased from a baseline of 18.1 (4.4) to 7.0 (4.1) at 1-hour, representing a mean decrease of 11.1 (5.2). This was statistically significant and exceeded the pre-specified 15% criterion, with 98.1% of the active group achieving a COWS score reduction of 15% or greater. The mean reduction was significantly greater in the active NET group (-11.13) than the sham group (-8.75), with a between-group difference of 15%. This equates to a 61% reduction in the active group compared to 46% in the sham group, indicating a 15% improvement with the device. |
| Safety: No increase in adverse events compared to predicate device. | Achieved: "There were no device-related adverse events (ADEs, or UADEs)." The risk profiles for the subject and predicate devices are comparable, both using transcutaneous nerve stimulation delivered through non-invasive earpieces without skin puncture. Clinical testing in 108 subjects demonstrated treatment tolerability and that identified risks (e.g., skin burns, irritation) have not increased. |
| Technological Equivalence: Substantially similar technological characteristics and principles of operation to predicate. | Achieved: The NET Device has the same general intended use and similar indications, technological characteristics, and principles of operation (auricular transcutaneous electrical stimulation) as the predicate (Sparrow Therapy System). Notable differences (bilateral vs. unilateral stimulation, higher instantaneous electrical output, higher frequency range) were evaluated and determined not to raise new questions of safety or effectiveness as demonstrated by non-clinical and clinical testing. |
2. Sample size used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective)
- Sample Size for Test Set: 108 participants.
- Active group: 53 participants
- Sham group: 55 participants
- Data Provenance:
- Study Type: Prospective, randomized, parallel-group, sham-controlled, superiority study.
- Country of Origin: One US site.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts (e.g. radiologist with 10 years of experience)
The "ground truth" in this study is the Clinical Opiate Withdrawal Scale (COWS) score. The document states that COWS scores were measured, but it does not specify the number of experts or their qualifications for assessing these scores. It's implied that trained clinical personnel (nurses, physicians) administered the COWS assessments as standard practice for such a study, but no specific details are provided.
4. Adjudication method (e.g. 2+1, 3+1, none) for the test set
The document does not describe any specific adjudication method for the COWS scores in the test set. It is standard for COWS assessments to be performed by a single trained clinician at each time point, so a multi-reader adjudication method would be unusual for this type of scale.
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
An MRMC comparative effectiveness study was not done. This study is not evaluating an AI algorithm assisting human readers, but rather a direct therapeutic device (transcutaneous alternating current stimulator) and its effect on opioid withdrawal symptoms, compared to a sham control. Therefore, there is no discussion of human readers or AI assistance.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
This question is not applicable. The NET Device is a therapeutic medical device, not an AI algorithm. Its performance is directly observed in patients, not as an algorithm-only output.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.)
The primary "ground truth" used for effectiveness was the Clinical Opiate Withdrawal Scale (COWS) score, which is a standardized, clinician-rated assessment of opioid withdrawal severity. This is a form of expert assessment by trained clinical personnel.
Secondary outcomes included:
- Cumulative inpatient MOUD (Medications for Opioid Use Disorder) utilization.
- Illicit opioid use during the outpatient phase (measured by oral fluid drug screen or timeline follow-back interview).
- Presence of device-related adverse events for safety.
8. The sample size for the training set
This question is not applicable. The NET Device is a physical medical device, not a machine learning model, so there is no "training set" in the context of AI/ML. The clinical study described is a pivotal trial to demonstrate safety and effectiveness for regulatory clearance, not for training an algorithm.
9. How the ground truth for the training set was established
This question is not applicable, as there is no training set for an AI/ML algorithm.
§ 882.5896 Percutaneous nerve stimulator for substance use disorders.
(a)
Identification. A percutaneous nerve stimulator for substance use disorders is a device that stimulates nerves percutaneously to aid in the reduction of withdrawal symptoms associated with substance use disorders.(b)
Classification. Class II (special controls). The special controls for this device are:(1) The patient-contacting components of the device must be demonstrated to be biocompatible.
(2) Electromagnetic compatibility and electrical, mechanical, and thermal safety testing must be performed.
(3) Electrical performance testing of the device and electrodes must be conducted to validate the specified electrical output and duration of stimulation of the device.
(4) Software verification, validation, and hazard analysis must be performed.
(5) Sterility testing of the percutaneous components of the device must be performed.
(6) Shelf life testing must be performed to demonstrate continued sterility, package integrity, and device functionality over the specified shelf life.
(7) Labeling must include the following:
(i) A detailed summary of the device technical parameters;
(ii) A warning stating that the device is only for use on clean, intact skin;
(iii) Instructions for use, including placement of the device on the patient; and
(iv) A shelf life.