All research grade systems have timers, automatic ramp up/down, continuous impedenance monitoring, low battery indicator and are IEC 60601 safety and EMC compliant.
What is consumer tDCS? Consumer tDCS devices are marketed directly towards users. They can be marketed simply as “tDCS” or for cognitive enhancement or for performance enhancement. They cannot be marketed for medical use, such as the treatment of a disease, since then they would be classified as medical devices. Once a consumer obtains a device, they can use their device for for any application. Consumer devices are cheaper then medical / research grade devices. The FDA has provided letters to companies like Thync and Halo; allowing them to market tDCS for consumer purposes without making claims on medical therapy.
What are the standards for Consumer tDCS? The quality of consumer devices varies. At the high end, devices such as Halo, Thync and ActivaDose are produced to the same standards as medical devices, they are just not cleared by the government for medical use and are not marketed by the companies for medical use. These products likely meet the “LOTES” guidelines. On the other extreme, there may be products that are not carefully designed or built. Poor design can mean things like not producing the correct output. Poor build simply means that products may be sent out with defects.
What is research grade tDCS? Research devices are those marketed for use in clinical trials. Research devices used in clinical trials must see the same design and manufacturing standards as clinical devices. This means, according to regulations in the US, Europe and other countries, devices tested on people need to be built to medical devices standards, even when they are not yet approved for use. For this reason, clinical and research grade devices are the same thing as far the devices themselves. The difference is simply how they are marketed. For example, the Soterix Medical 1x1 tDCS is marketed in the US for research but is approved and marketed in Europe for the treatment of depression, pain (migraine, fibromyalgia) and stroke rehabilitation.
What are the standards for Research and Medical grade tDCS? The standards that govern research and medical grade tDCS in the US are called FDA Quality Systems which rely on the rules by the IEEE organization. The comparable standards in Europe are part of the CE mark and relies on rules set by the IEC organization. But since the IEEE and IEC are almost identical, medical / research grade tDCS products usually meet standards across the US, Europe and other countries.
What is the difference in cost? Consumer devices range from about $80 to $500. Medical and research devices range from $300 to about $5,000 for top brand to over $10,000 for the more advanced High-Definition systems.
What about iontophoresis devices? An iontophoresis devices is cleared by the FDA or another country for the use of direct current stimulation to deliver ions or drugs to the body. When used without drugs, the delivery of ions is for all practical purposes the same thing as tDCS. The use of an iontophoresis device for tDCS treatment would be “off-label”.
What is HD-tDCS? HD-tDCS stands for High Definition transcranial Direct Current Stimulation. Regular tDCS uses relatively large electrodes (about 5x5 cm) while HD-tDCS uses relatively small electrodes (about 1x1 cm) which are gel filled. HD-tDCS is found only on Research / Clinical grade devices. HD-tDCS can be used with EEG to record brain activity.
Can the same device be a consumer and medical / research grade tDCS device? This can be complicated, but yes. The Thync device and the Fisher Wallace devices, neither of which are basic tDCS, have separate websites for consumer and medical use, but it's the identical device. Medical and research devices cannot be sold to consumers, though they can be provided via a medical care-giver. Bottom line, the devices listed below as Consumer can be bought by anyone, whereas the ones listed under Medical / Research, can only be bought by medical care-givers or researchers.
References
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