(90 days)
TENS stimulation is used for symptomatic relief and management of chronic intractable pain. It is also used as an adjunctive treatment in the management of post-surgical and post-traumatic pain. It has no curative value and should be used only in conjunction with medical supervision.
The CEFAR Primo is a handheld battery powered TENS device with two channels and nine preset stimulation programs. The two channels are separated and it is possible to stimulate with two different stimulation programs simultaneously, one on each channel. Program information and electrical current amplitude is displayed on a LCD. The user can set the amplitude in the range 0-60 mA for all programs.
Here's a breakdown of the acceptance criteria and study information for the CEFAR Primo, based on the provided document:
Acceptance Criteria and Device Performance
The document does not explicitly state formal "acceptance criteria" in terms of performance metrics (e.g., sensitivity, specificity, accuracy) that the device had to meet. Instead, the "acceptance criteria" appear to be centered on demonstrating substantial equivalence to a predicate device and compliance with relevant safety standards.
The study presented focuses on demonstrating that the CEFAR Primo performs equivalently to the predicate device and adheres to safety regulations, rather than meeting specific quantifiable performance targets.
| Characteristic | Acceptance Criteria (Implied by Predicate Comparison and Standards) | Reported Device Performance (CEFAR Primo) |
|---|---|---|
| Indications for Use | Must be identical or substantially similar to the predicate device to ensure equivalent intended medical purpose. | Identical to predicate device: "Used for symptomatic relief and management of chronic intractable pain. It is also used as an adjunctive treatment in the management of post-surgical and post-traumatic pain. It has no curative value and should be used only in conjunction with medical supervision." |
| Safety Standards Compliance | Must comply with relevant international electrical safety and electromagnetic compatibility (EMC) standards for medical devices (IEC EN 60601-1-2, IEC EN 60601-1, and IEC EN 60601-2-10). The device must not present new safety concerns. | Successfully completed external testing, performed by Notified Body SEMKO AB, confirming compliance with IEC EN 60601-1-2 regarding EMC, IEC EN 60601-1 regarding general safety, and IEC EN 60601-2-10 regarding TENS device safety. |
| Functional Equivalence | Key functional characteristics (e.g., number of channels, open circuit detection, current delivery, display, power supply, output control, pulse form, and maximum parameters like amplitude, pulse width, and charge per pulse) must be comparable to the predicate device to ensure equivalent therapeutic effect and user experience. Some variations are acceptable if they do not raise new safety or effectiveness concerns. | Identical or comparable in: |
- Indications for use
- Prescription device
- Number of channels (2)
- Open circuit detection (Yes)
- Transcutaneous current delivery (Yes)
- LCD display (showing intensity & program)
- Power supply (battery operated)
- Software controlled output (Yes)
- User control of output (push buttons)
- Pulsed output (Yes)
- Pulse form (Asymmetric biphasic, zero net DC)
- Max amplitude (60 mA)
- Max pulse width (180 µs vs 300 µs for predicate)
- Max charge per pulse (10.8 µC vs 18 µC for predicate)
Differences noted but deemed acceptable: - Specific preset stimulation programs/parameters (e.g., continuous, burst, modulated pulse duration, mixed frequency) offer different specific settings but are within the general functional scope of a TENS device. |
| (Implied) No New Concerns | The device must not raise any new questions of safety or effectiveness compared to the predicate device. | Conclusion: The CEFAR Primo "presents no new concerns about safety and effectiveness." |
Study Information
The document describes a bench testing and comparison study rather than a clinical trial or a study involving human readers.
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Sample Size used for the test set and the data provenance:
- Test Set Sample Size: The document does not specify a "sample size" in the context of clinical data or image sets. The study involved in-house system validation and external testing against technical standards. It's an assessment of the device's physical and electrical properties, not its performance on patient data.
- Data Provenance: Not applicable, as it's a technical validation of a physical device against standards, not data-driven performance.
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Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
- Number of Experts: Not applicable in the sense of clinical experts establishing ground truth for diagnostic accuracy since this is a TENS device subject to technical safety and performance standards.
- Qualifications: The "experts" involved would be the engineers and technicians at CEFAR Medical AB for in-house validation, and the testing personnel at SEMKO AB (ID 0413), a Notified Body, for external compliance testing. Their qualifications would be in electrical engineering, medical device safety, and regulatory compliance.
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Adjudication method for the test set:
- Not applicable. Adjudication methods like 2+1 or 3+1 are used for reconciling expert opinions on clinical ground truth. This study relies on objective measurements against engineering standards.
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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 study was done. This device is a Transcutaneous Electrical Nerve Stimulator (TENS), not an AI-powered diagnostic tool. Therefore, the concept of "human readers improve with AI vs without AI assistance" does not apply.
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If a standalone (i.e. algorithm only without human-in-the-loop performance) was done:
- Yes, a standalone study was done, but not in the context of an algorithm. The "standalone" performance here refers to the device's intrinsic functional and safety characteristics as measured against technical standards, independent of human interaction beyond normal operation. The device itself (the "algorithm only") was tested for its electrical output, safety features, and compliance with regulations.
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The type of ground truth used:
- The "ground truth" for this regulatory submission is defined by international medical device safety and performance standards (IEC EN 60601-1-2, IEC EN 60601-1, IEC EN 60601-2-10) and the functional characteristics of the predicate device (SMP-PLUS K982410 TENS-stimulator Rehabilicare). The device's measurements and functionalities were compared against these established technical benchmarks and the predicate device's specifications.
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The sample size for the training set:
- Not applicable. This is not a machine learning or AI device that requires a training set.
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How the ground truth for the training set was established:
- Not applicable. No training set was used.
§ 882.5890 Transcutaneous electrical nerve stimulator for pain relief.
(a)
Identification. A transcutaneous electrical nerve stimulator for pain relief is a device used to apply an electrical current to electrodes on a patient's skin to treat pain.(b)
Classification. Class II (performance standards).