(154 days)
Flex Max by Stendertone is indicated for the improvement of abdominal muscle tone, for strengthening of the abdominal muscles and for the development of a firmer abdomen.
Flex Max by Slendertone, Type 517-US is a two-channel battery operated muscle stimulation, system specifically designed to exercise the abdominal muscles. It offers 10 programs to the user and comprises of two main components, an electronic stimulator module which generates the required stimulation signals and an abdominal electrode belt, which connects the signals from the stimulator to the skin electrodes located on the inner surface of the belt. The product is supplied with a double set of double-sided adhesive electrodes, a double set of batteries, an extender belt and an instruction manual. Power is derived from 3 x 1.5 volt (LR03) batteries located in a compartment protected by a removable battery cover. Instructions are provided in the user instructions. For purposes of hygiene, the garment may be cleaned and instructions for device care are included in the user manual.
Here's an analysis of the provided text regarding the acceptance criteria and supporting study for the Flex Max by Slendertone, Type 517-US:
It's important to note that the provided documentation is a 510(k) Premarket Notification for a medical device. This type of submission focuses on demonstrating substantial equivalence to a previously legally marketed device (predicate device), rather than a full de novo clinical trial proving efficacy and safety from scratch.
Therefore, the "acceptance criteria" here are primarily about demonstrating that the new device is as safe and effective as the predicate device, not necessarily defining specific performance metrics for muscle tone improvement. The "study that proves the device meets the acceptance criteria" refers to the entire 510(k) submission process, which relies on demonstrating equivalence rather than a dedicated clinical trial for performance.
1. Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criteria (Demonstrated Equivalence to Predicate) | Reported Device Performance (as demonstrated in submission) |
|---|---|
| Intended Use: Same intended use as predicate device | "The Flex Max by Slendertone device has the same intended use and indications for use as the listed equivalent legally marketed device. It is intended for use by healthy persons to apply transcutaneous neuromuscular electrical stimulation ('NMES') through skin contact electrodes for the purpose of improving abdominal muscle tone, strength and firmness." |
| Indications for Use: Same indications as predicate | "Flex Max by Stendertone is indicated for the improvement of abdominal muscle tone, for strengthening of the abdominal muscles and for the development of a firmer abdomen." |
| Technological Characteristics: Substantially equivalent to predicate | "The Flex Max by Slendertone device is identical to the predicate device in design, materials, mode of operation, and methods of manufacture. It differs only in the addition of different program offerings to the user." |
| Safety: Compliance with relevant electrical safety and EMC standards | "The Flex Max by Slendertone complies with international standards for electrical safety and electromagnetic compatibility." |
| Effectiveness: Inferred from equivalence to predicate | Implied to be equivalent to the predicate device's effectiveness through the demonstration of identical design, materials, mode of operation, and methods of manufacture. |
Explanation of "Acceptance Criteria" in this context: For a 510(k) submission, the primary "acceptance criterion" is to demonstrate substantial equivalence to a predicate device. This means showing that the new device has the same intended use, indications for use, and similar technological characteristics, and that any differences do not raise new questions of safety or effectiveness. The device met this acceptance criterion, as indicated by the FDA's "substantial equivalence" determination.
2. Sample size used for the test set and the data provenance
- Sample Size for Test Set: Not applicable in the context of a new clinical study. The submission primarily relies on the established safety and effectiveness of the predicate device (Slendertone Flex, Type 515, K030708). No new clinical "test set" data from human subjects is provided beyond proving the new device's equivalence to the predicate.
- Data Provenance: Not applicable. No new human data is presented in this submission. The basis for equivalence is drawn from the predicate device’s prior clearance.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts
- Number of Experts: Not applicable. No "ground truth" was established for a new clinical test set in this submission.
- Qualifications of Experts: Not applicable.
4. Adjudication method (e.g. 2+1, 3+1, none) for the test set
- Adjudication Method: Not applicable. No clinical test set requiring adjudication was performed as part of this 510(k) submission.
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
- MRMC Study: No. This is a muscle stimulator device, not an imaging/diagnostic device that would typically involve human "readers" or AI assistance in that sense.
- Effect Size of Human Readers with/without AI: Not applicable.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
- Standalone Performance: Not applicable. This device is a muscle stimulator, not an algorithm. Its operation inherently involves a human user applying it.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc)
- Type of Ground Truth: The "ground truth" in this context is the FDA's prior determination of safety and effectiveness for the predicate device. The submission's "proof" relies on demonstrating that the new device is functionally identical or equivalent to this already cleared predicate device. There is no new clinical outcomes data or pathology presented for the Flex Max.
8. The sample size for the training set
- Sample Size for Training Set: Not applicable. This is not an AI/machine learning device that requires a training set.
9. How the ground truth for the training set was established
- Ground Truth for Training Set: Not applicable.
Summary of the Study:
The "study" described in the provided document is a 510(k) Premarket Notification submission, not a clinical trial. The manufacturer's strategy was to demonstrate substantial equivalence to a previously cleared predicate device (Slendertone Flex, Type 515, K030708).
- Key Argument: The device is "identical to the predicate device in design, materials, mode of operation, and methods of manufacture," differing only in "the addition of different program offerings to the user."
- Clinical Testing: "No additional clinical studies were provided as part of this submission." This indicates that the manufacturer relied entirely on the established safety and effectiveness of the predicate device and the similarity of the new device to the predicate, along with compliance with international electrical safety and electromagnetic compatibility standards.
- Ground Truth: The "ground truth" for the overall acceptance of the device is rooted in the FDA's previous clearance of the predicate device. By demonstrating substantial equivalence, the new device is deemed to carry the same safety and effectiveness profile as the predicate.
In essence, the "study" for this 510(k) submission primarily involved a technical comparison and regulatory compliance assessment to demonstrate that the Flex Max by Slendertone is sufficiently similar to an already approved device, making new clinical performance data unnecessary for its market clearance.
§ 890.5850 Powered muscle stimulator.
(a)
Identification. A powered muscle stimulator is an electrically powered device intended for medical purposes that repeatedly contracts muscles by passing electrical currents through electrodes contacting the affected body area.(b)
Classification. Class II (performance standards).