Mods, if I still may update this thread, there are some interesting new developments. Per The Atlantic:
Another example of an age-old old-age technology with an uncertain but potentially promising future is Personal Emergency Response Systems (PERS) devices, which often take the form of an emergency-call necklace that can summon help in the event of a fall. Just 2 percent of the U.S.’s 65-plus population subscribe to such services. Part of the issue may be cost, but in the United Kingdom, where the National Health Service foots the bill for consumers, the adoption rate is still a lackluster 16 percent. If the main problem isn’t cost, it may have to do with self-image. As Pew reported in 2009, only 35 percent of people 75 and up say they feel old; 100 percent, though, it’s safe to assume, recognize that PERS are for older adults. People are dying as a result of this disconnect—because they fail to obtain a much-needed PERS device or else, if they have one, because they refuse to use it.
Disturbingly, in one small 2010 German study, 83 percent of PERS wearers who laid on the floor for at least 5 minutes after taking a fall failed to press the button to summon help. It wasn’t because they couldn’t physically press it, many later explained—it was that they simply wanted to manage the situation themselves, with no help from emergency services. That revealed preference suggests a product concept that is every bit as broken as hearing aids: something few want to own, and even fewer want to use.
Happily, however, an answer may once again be on the way, in the form of genre-bending technologies. The smartphone is one early PERS challenger. Even though a PERS device is perhaps the easiest product to use in the event of an emergency, a cellphone is arguably a better emergency technology for the simple reason that people actually go out of their way to own them, carry them on their person, and use them. It’s easy to see why: Whereas a PERS device signifies a decline into isolated dependency, a cellphone represents a healthy social network at one’s fingertips. As of 2014, 77 percent of Americans 65 and older own cellphones, making smartphone fall-detection apps that much more promising.
But a perhaps even bigger improvement on PERS is still on its way. Dina Katabi, a colleague of mine at MIT, has developed a fall-detection system that relies on wifi-like radio signals to determine—through walls—whether someone is upright and breathing in their home. Currently, Emerald, as it’s known, is a standalone technology that is not yet on the market, but it’s easy to imagine it or something like it finding its way into smart-home hubs like the Amazon Echo or Google Home. Soon, such devices could alert emergency services if users take a nasty spill, experience a stroke, or choke on an olive pit while home alone (something that can happen at any age), obviating traditional PERS setups.