Class Action Lawsuit Filed Against Fitbit For 'Highly Inaccurate' Heart Rate Trackers (nbcnews.com) 146
An anonymous reader quotes a report from NBC News: A class action lawsuit against Fitbit may have grown teeth following the release of a new study that claims the company's popular heart rate trackers are "highly inaccurate." Researchers at the California State Polytechnic University, Pomona tested the heart rates of 43 healthy adults with Fitbit's PurePulse heart rate monitors, using the company's Surge watches and Charge HR bands on each wrist. Subjects were then hooked up to a BioHarness device that produced an electrocardiogram (ECG), to record the heart's rhythm against the data being produced by Fitbit's devices. Comparative results from rest and exercise -- including jump rope, treadmills, outdoor jogging and stair climbing -- showed that the Fitbit devices miscalculated heart rates by up to 20 beats per minute on average during more intensive workouts. The study was commissioned by the Lieff Cabraser, the law firm behind the class action suit that is taking aim at three Fitbit models that use the PurePulse heart monitor, including the Fitbit Blaze, Fitbit Charge HR and Fitbit Surge. "What the plaintiffs' attorneys call a 'study' is biased, baseless, and nothing more than an attempt to extract a payout from Fitbit. It lacks scientific rigor and is the product of flawed methodology," Fitbit said in a statement posted by Gizmodo.
Didn't take long..... (Score:3)
Wow...only a day or so after that study was released and the lawyer vultures are already circling.... smh...
Re: (Score:3)
What's particularly fishy... (Score:4, Insightful)
The lawyers sponsored the study, and it looks like it's actually pretty decent methodology--comparing the pulse from the EKG (which I certainly hope is reliable) to the FitBits on the wrists at the same time means you've got one of the gold standards of study design, since the pulse ought to be the same in the same person no matter what point you measure it from (and how you measure it) so you make it a lot easier to analyze the data. You've controlled both for the issues if you used different subjects and for if you measured at different times, so the only real question when doing the analysis is "How well do the parts of each set align?" (You do multiple subjects to make sure you didn't have something rather weird happen like somebody somehow pulling off 'different pulse depending on where measured,' and the number looks actually rather good--a bit more subjects than I'd expect a study like this without money being thrown at it to have, actually.)
The only thing that seems particularly weird here is that I'd have expected the company to have sponsored this study or something very much like it during its own R&D cycle, because it would be both good for marketing and good practices. Doing this sort of basic study is pretty...basic, if you're trying to make something that monitors {foo}. About the only reason I could see for not doing that would be "FDA might get panties in a wad," except that is something that I'm amazed hasn't happened already...and I would be wanting to develop a medical-grade version anyway. It should sell, especially if I can add in remote monitoring; that would probably net me sales to both health care facilities and in professional sports...
Re: (Score:1)
Yeah, but of course the lawyers for Fitbit are going to say it's a bad study. One, they are supposed to zealously defend their client, and two, they're hardly likely to fold this early in this thing, based off of one study, no matter how accurate it may be. Attack by opinion is the unfortunate standard.
Re: (Score:2)
Yeah, but of course the lawyers for Fitbit are going to say it's a bad study. One, they are supposed to zealously defend their client, and two, they're hardly likely to fold this early in this thing, based off of one study, no matter how accurate it may be. Attack by opinion is the unfortunate standard.
Of course they won't want to fold early! The lawyers on both sides will be milking their clients for all they are worth!
Re: (Score:2)
Re: (Score:2)
IANAL ... but it's my understanding that in most cases the costs for class action lawsuits is fronted by the law firm and they get a large cut of the settlement in recompense. So it's in the "plaintiff" firms' interest to secure a fast settlement.
I'd think that the size of the cut of the settlement might be linked to the amount of time the law firm spent on the case? Or is it set up front?
Re: (Score:2)
Re: (Score:2)
Consumer Reports took a second look [consumerreports.org] at their FitBit review, using a different (and apparently better) heart monitor harness than the claimed study. They did find a few discrepancies, but far smaller, landing within 3 beats per minute in almost all cases. They also noted that when the FitBit is worn a couple of inches above the wrist instead of on the wrist, as FitBit suggests but which many people seem to not know, the results are more accurate. CR is monitoring the case, but they have elected to not cha
Re: (Score:2)
https://www.fitbit.com/chargeh... [fitbit.com]
(all the way at the bottom of the page)
Heart Rate
Like all heart rate monitoring technologies, accuracy is affected by physiology, location of device, and different movements. Learn more about wear during workouts.
The directions state clearly that you should wear it two inches above your wrist during workouts, and the "Learn more" line links to information about this:
https://www.fitbit.com/purepul... [fitbit.com]
I never expected the Fitbit to be equivalent to a medical heart rate monitor, but I wouldn't expect to pay $130 for a medical scanner either. It seems to me that this is a frivolous case, as Fitbit never claimed their sensors were accurate compared t
Re: (Score:2)
I would be wanting to develop a medical-grade version anyway
I doubt you would want to do that. It's very, very, very expensive and has a tiny market. Fitbit is a hobby device; it was intended to give a rough estimate of your activity as a motivational tool. It is not a medical device and never will be.
Re: (Score:1)
It claims to monitor pulse. As such, it will be used by people who want to monitor their pulse. If it was advertised as "roughly estimating" pulse, no hobbyist would buy it because it would be less useful than the fingertips and watch method.
The vast majority of habitual exercisers have the resources they need to estimate their pulse to the accepted medical standard (beats per minute), the demographic of people exercising who lack fingers or arteries is very small.
Also, elsewhere in this discussion are ma
Re: (Score:2)
https://www.fitbit.com/chargeh... [fitbit.com]
Scroll all the way down that page, and read the Heart Rate paragraph. If you expect it to be extremely accurate, it is you that is expecting something false, Fitbit does not sell them as medical devices, and make no claims of accuracy.
Re: (Score:2)
I would be wanting to develop a medical-grade version anyway
I doubt you would want to do that. It's very, very, very expensive and has a tiny market. Fitbit is a hobby device; it was intended to give a rough estimate of your activity as a motivational tool. It is not a medical device and never will be.
I do know both the 'very, very, very expensive' part and the 'tiny market' part already.
However, part of why that 'tiny market' is because it's a hobby device and as such expensive for what it does. A medical-grade version gets at a different tiny market...but at least part of it has deep pockets. Think about just how much money goes into professional athletes--the medical-grade version would almost certainly be a pretty minimalist device, to cut down on R&D and certification costs, but remote monitor
Re: (Score:2)
A medical-grade version gets at a different tiny market...but at least part of it has deep pockets. Think about just how much money goes into professional athletes--the medical-grade version would almost certainly be a pretty minimalist device, to cut down on R&D and certification costs, but remote monitoring of athletes' vitals is pretty much going to become a thing.
Too bad then that you can buy a medical grade pulse measurement for $100. The only downside is wearing a chest strap (not a big ask for a workout). That is what they were using as their accurate baseline to compare these fitbits to.
Wrist based measurement will never be as accurate (especially while being knocked around on the sporting field) as chest strap based monitors. Any serious athlete knows this and has a PROPER heart rate monitor for their sport.
Disclosure: Professional level athlete. I wear a wrist
Re: (Score:2)
It would come down to whether or not Fitbit advertisement is a false advertising. Otherwise, I am not sure how these lawyers would win the law suit...
Re: (Score:2)
A medical-grade version gets at a different tiny market...but at least part of it has deep pockets. Think about just how much money goes into professional athletes--the medical-grade version would almost certainly be a pretty minimalist device, to cut down on R&D and certification costs, but remote monitoring of athletes' vitals is pretty much going to become a thing.
Too bad then that you can buy a medical grade pulse measurement for $100. The only downside is wearing a chest strap (not a big ask for a workout). That is what they were using as their accurate baseline to compare these fitbits to.
I've also seen how those go if you're trying to remotely monitor--unless they've finally gone wireless? It's been a while since I last checked in there, since it's not quite my field.
Wrist based measurement will never be as accurate (especially while being knocked around on the sporting field) as chest strap based monitors. Any serious athlete knows this and has a PROPER heart rate monitor for their sport.
Disclosure: Professional level athlete. I wear a wrist based smart watch for sleep tracking and resting heart rates etc. (where wrist is appropriate). I take this off for my sport and wear a chest strap band and Garmin watch. The right tool for the right job.
Honestly I'd not design it for the wrist, either--it seems gimmicky, too vulnerable, and I know from personal experience that there are some people who you have to check their pulse elsewhere if you want to find it reliably...because I'm one of those people. The main goal would be remote monitoring, and preferably more than j
Re: (Score:2)
I got a fitbit ChargeHR (Christmas present) I wear the device pretty regularly and while exercising and my experience is the pulse readings during exercise is highly suspect. When I'm on the treadmill the ChargeHR frequently reads 10-30 bpm higher than the treadmill sensors. Fitbit is not a medical-grade device, if you need that level of accuracy for health reasons, don't get a fitbit.
Steps and stairs are measured by motion sensors on your arm, so accuracy varies there too; don't bet money on it, you can ea
Re: (Score:2)
my experience is the pulse readings during exercise is highly suspect. When I'm on the treadmill the ChargeHR frequently reads 10-30 bpm higher than the treadmill sensors. Fitbit is not a medical-grade device, if you need that level of accuracy for health reasons, don't get a fitbit.
I call foul on this. Is your treadmill a "medical-grade device"? No, of course it isn't. So why are you willing to accept such erroneous readings from the Fitbit when the consumer-grade treadmill apparently is able to get rea
Re: (Score:2)
OKay when I put my hot sweaty highly conductive hands on an electrical sensor and it agrees with what I feel physiologically, vs. an optical sensor trying to detect doppler shifts in blood capillaries while bouncing around on a wrist band while
I'm bouncing on a treadmill that gives a reading that doesn't agree with what I'm feeling physiologically, I'm going with the electrical.
Re: (Score:2)
Re: (Score:2)
They also seem to hate sweat. When I work out on a stationary bike, my Charge HR records my heart rate slowly rising up until I start perspiring heavily. Once my wrist is wet, the heart rate reading plummets by about 30 bpm and stays low for the rest of the workout. The rate seems to lock onto the pedal speed as the RPM displayed on the bike is almost identical to the heart rate being recorded. When I run it sometimes locks onto my foot strikes instead of heartbeats.
At the end of the day, it doesn't matter
Re: (Score:2)
Are you wearing it as shown in the instructions...high up from your wrist? Is it sliding down? I've been wearing the same model for about 4 months. It's generally okay, but that's all I expected for the price. I've had to adjust my stride length because their default was way low for me....I compared it's results with my Garmin 620 GPS watch.
Re: (Score:2)
Re: (Score:2)
Yeah, it brought new meaning to the term YMMV when I ran 5 miles (measured by my Garmin), but the Charge said it was less than 4. It's also hit or miss on stairs (hit maybe 80-90% of the time). I've also noticed that the tracking doesn't catch any incline on the gym treadmill, no matter how steep (though I get about 25 flights of stairs counted on my 5 mile park runs...it is hilly), and counts next to no steps on an elliptical. I'm still debating if I'll replace it with a new one with the time comes. It
Re: (Score:2)
The big problem with attacking the methodology here is that if they call the bluff and make improvements to the methodology, the results aren't going to change and Fitbit knows that, or should know it based on their own information. Plus, as part of the lawsuit they're going to have to release to the opposing lawyers the information they have about the accuracy of the devices; is this study more accurate than their own (also self-funded!) data? Did they even do the testing to have a basis for believing thei
Re: (Score:1)
Sure enough. It was.
Overpriced fad gadgets turn out to be crap (Score:2)
I was not sad to see fools parted with their money here except when employers started buying into them and tying health care costs to inaccurate electronic tethers. After a couple of those experiences, I know the technical groups I worked in learned how inaccurate these things were, or gamed the telemetry systems behind them (hint: their web services are usually crap/hackable) so they could avoid health care price increases without actually taking th
This is not possible. (Score:5, Funny)
These devices were designed by Nathan Myhrvold. They are accurate but you have the wrong pulse.
Re: (Score:1)
Right... Companies shouldn't be held accountable just because they made a crap product that advertises functionality that it doesn't have. It's all those idiot users' fault for believing that consumer protection laws should require a product to do what is advertised.
Re:Overpriced fad gadgets turn out to be crap (Score:4, Insightful)
Right... Companies shouldn't be held accountable just because they made a crap product that advertises functionality that it doesn't have. It's all those idiot users' fault for believing that consumer protection laws should require a product to do what is advertised.
FitBit and others did not claim to be medical devices but rather a way to keep track of your activity as part of a wellness regime. Now, a paid study finds that they are not as accurate as medical devices and somehow the company is defrauding the consumer? I have a number of issues with FitBit including their desire to have me send them my exercise information rather than just load it into the app and they are itchy and uncomfortable. It would be nice to see the raw data on which the conclusions are based to see what "up to 20 beats" really means and how accurate FitBit is in various situations.
I would expect if someone is undergoing a severe exercise regimen the would carefully research the tools they use to track vital signs to ensure their safety. If I were on a jury and someone said "I was injured because my FitBit didn't tell me my heartbeat was too high while I did this extreme workout..." I'd respond with a "Sorry, but the legal system can't fix stupid, but mother nature can and did" judgement.
Part of the problem is we expect computers to be precise and accurate and they often are not, and when they aren't people get upset instead of adjusting their expectations.
Re: (Score:2)
Right... Companies shouldn't be held accountable just because they made a crap product that advertises functionality that it doesn't have. It's all those idiot users' fault for believing that consumer protection laws should require a product to do what is advertised.
FitBit and others did not claim to be medical devices but rather a way to keep track of your activity as part of a wellness regime. Now, a paid study finds that they are not as accurate as medical devices and somehow the company is defrauding the consumer? I have a number of issues with FitBit including their desire to have me send them my exercise information rather than just load it into the app and they are itchy and uncomfortable. It would be nice to see the raw data on which the conclusions are based to see what "up to 20 beats" really means and how accurate FitBit is in various situations.
"Up to 20 beats" is best considered in light of a pulse chart like this one [nih.gov]. The normal resting pulse of an adult is somewhere between 60 to 100 beats per minute--a well-trained athlete's resting pulse would be in the 40 to 60 range. Presuming the FitBit uses the same measure--which is the standard one--then being off by 20 beats is not negligible at utter best...though the summary suggests that it is not actually consistent in its error, which is really concerning since people are typically pushed to get
Re: (Score:2)
I would be with you if I was on that jury for the case you give as an example, but what about if it was someone saying they were financially harmed because their employer-required FitBit keeps saying they're pushing their heart rate dangerously high or not high enough?
That would be different, IMHO. If someone is using the data, other than the person wearing the FitBit, to make recommendations or levy use / target requirements on an employee then they are accepting legal responsibility for any adverse outcomes.
(The best solution would be to flat-out forbid employers from requiring these things, but given that if they're even vaguely accurate and reliable then they may be already a violation of medical privacy laws... The question may really be one of who actually gets to take it to court.)
I agree. Using a consumer device for medical decisions is clearly not a good practice. It's one thing to make it voluntary but requiring it steps, again IMHO, into the realm of medical advice and subject to privacy laws such as HIPAA and needs to be treated as such.
Re:Overpriced fad gadgets turn out to be crap (Score:4, Informative)
Right... Companies shouldn't be held accountable just because they made a crap product that advertises functionality that it doesn't have. It's all those idiot users' fault for believing that consumer protection laws should require a product to do what is advertised.
The company's website has a lot to say [fitbit.com] about how the type of exercise, range of motion, and the way the device is worn can affect the accuracy of heartbeat measurement, and they make no claims at all regarding measurement accuracy. It doesn't appear to me that they are advertising great accuracy at all. Aside from that, this is not a case of the company running afoul of consumer protection laws; it's a case of lawyers seeking a profit from a dodgy class-action suit. The consumers who were putatively damaged won't see much in the way of an award, which is the norm in cases like this.
Re: (Score:3)
Right... Companies shouldn't be held accountable just because they made a crap product that advertises functionality that it doesn't have. It's all those idiot users' fault for believing that consumer protection laws should require a product to do what is advertised.
The company's website has a lot to say [fitbit.com] about how the type of exercise, range of motion, and the way the device is worn can affect the accuracy of heartbeat measurement, and they make no claims at all regarding measurement accuracy. It doesn't appear to me that they are advertising great accuracy at all. Aside from that, this is not a case of the company running afoul of consumer protection laws; it's a case of lawyers seeking a profit from a dodgy class-action suit. The consumers who were putatively damaged won't see much in the way of an award, which is the norm in cases like this.
What's the damage though? Like you say it's a device that gives you and indication of what your heartrate is. I've never heard them (or apple etc) guarantee any kind of accuracy and they don't claim it's medical grade in the slightest. With all that though. What its the damage this class action seeks to compensate? It seems if you need to know your exact heart rate for whatever reason, a fitbit might not be the right tool for the job.
Re: (Score:2)
As a fitbit Charge HR user, I did my research before hand. I wanted something to help me monitor my workouts, and keep an eye on my pulse rate, to keep in a a range. As well as to motivate me a bit more. Which it has.
That being said. I did a lot of research on which one to get, the biggest complaint of the (at the time brand new) device was the accuracy of the heart rate monitor. There were even medically trained people saying that the method and how it is held in place is inherently inaccurate. They
Re: (Score:2)
Re: (Score:2)
FitBit has always claimed their ChargeHR is not as accurate during intensive exercise. They're pretty accurate at resting heart rate and when casually walking, but not when you're driving close to MHR. The lawyers found the same thing, and concluded that consumers are being defrauded because FitBit advertises having a heart rate monitor.
Re: (Score:2)
If it's advertised as a fitness aid (it even has "fit" in the name!) or as helping with exercise, and that is exactly when it fails, then that is a potentially fraudulent product; and not because it isn't a medical device.
If it was good at measuring during exercise, but was inaccurate at rest, then that might not be a problem. After all, it is a fitness aid, not a heart monitor...
Fine print doesn't always help, either.
Re: (Score:2)
It doesn't fail as a fitness device. They acknowledge that spot-measurement of heart rate may be inaccurate; and also cite that such inaccuracies--even severe ones--don't affect its ability to use HRM data to calculate calories burned because it uses that data to measure statistical trends. In other words: FitBit isn't measuring (b) BPM and correlating that to (c) calories; it's measuring increases, decreases, and stable levels in heart rate, and determining if you're exerting yourself or not, and by ho
Re:Overpriced fad gadgets turn out to be crap (Score:5, Interesting)
Overpriced fad gadgets turn out to be crap - film at 11.
They may indeed be crap, but the crappy article provides no actual information about that. First, it says it is inaccurate by an average of "up to" 20 beats per minute. "Up to" means "less than", so that statement would be true even if the deviation was zero. So why don't they just say what the average deviation is, instead of using meaningless weasel words? Then later in the article, they talk about an error of "20 or 30" beats per minute. So which is it? Less than 20, or 20 to 30? TFA was written by someone willing to twist both words and numbers to push an agenda.
Re: (Score:2)
"Then later in the article, they talk about an error of "20 or 30" beats per minute."
It's a bit weaselier than that. The article never suggests that the device is off by 20-30 bpm, but actually reads:
"Calculating a heart rate that's off by 20 or 30 beats per minute can be dangerous - especially for people at high risk of heart disease."
So they first make a meaningless claim (that the device can be off by "up to 20" bpm) and follow it up with a non-sequitur about the danger of errors between 20 and 30 bpm.
I
Re: (Score:1)
Try looking at the actual study:
http://www.lieffcabraser.com/p... [lieffcabraser.com]
Did you really expect a news article to represent it accurately 8-/?
Re: (Score:2)
I thought it was common knowledge that bracelet heart-rate meters were unreliable.
That's why so many of us still buy those chest straps (also bluetooth now).
Next thing, we will be shocked, shocked to hear that those body-fat reading scales are a lot of junk.
Re: (Score:2)
Body fat estimating scales don't claim to "read" or otherwise measure body fat. They only claim to estimate what it would be in the average person with the same height/weight/age or whatever inputs it has.
But if the claim in the advertising when read using the words in the actual ad is not true, that is bigger deal. "Gosh, I saw some other products that also lied about what they do" isn't a defense that is likely to be worth the time saying it; even if you found a better example.
The question here isn't "is
Re: (Score:2)
Yes they do. A "proper" one measures bioelectrical impedance. Muscle conducts better than fat.
Re: (Score:2)
And...the information collected by corporations from these things is generally considered to be exempt from HIPAA because it's "fitness information" not "medical information". We've heard the rules of the game.
However, there's a lot of money at stake here because corporations are using these things to decide who should pay more or less for health plans, and the more unscrupulous companies may also be using everyone's "op
Re: (Score:2)
"not intended to be scientific or medical devices" (Score:2)
Well, then. I was thinking of getting one to help me get and stay close to max-rate for interval training. 14% inaccuracy would be wildly dangerous in that case.
The lawyers may be scum, but I'm glad to have read these articles.
Comment removed (Score:4, Interesting)
Re:"not intended to be scientific or medical devic (Score:4, Insightful)
"Well, then. I was thinking of getting one to help me get and stay close to max-rate for interval training. 14% inaccuracy would be wildly dangerous in that case."
I do hope you're being sarcastic. If not then you might want to consider listening to your body instead of reliying on some stupid device. You know, what athletes people have done for millenia. If you're so disconnected from what your body is telling you perhaps you shouldn't be training at all.
Welcome to the health industry (Score:3)
Expect the prices of these things to soar as their liability insurance costs far outweigh their costs of production and advertising.
Re: (Score:1)
As they had a $358 million IPO, that dingdong thought "Hey, I bet I can make a lot of money."
Re: (Score:2)
As they had a $358 million IPO, that dingdong thought "Hey, I bet I can make a lot of money."
358 million is just a drop in the bucket when the full effects of the liability exposure kicks in.
Re: (Score:3)
Liability? LOLWUT? Liability is irrelevant! The execs' cut is already in an offshore bank somewhere, so who cares if some meaningless paper entity has to declare bankruptcy? Privatize the profits, socialize the liabilities!
Re: (Score:2)
Liability? LOLWUT? Liability is irrelevant! The execs' cut is already in an offshore bank somewhere, so who cares if some meaningless paper entity has to declare bankruptcy? Privatize the profits, socialize the liabilities!
Then there goes the humans as part of the internet of things. I'm not talking about the CEO's, I'm talking about adding something to the long list of everything we sue about. CEO perks are something different.
Re: (Score:2)
I have to wonder what dingdong thought that making human health part of the internet of things was a good idea.
If you think consumer health data delivered via the internet is bad, I've got some really bad news for you. There are many commercial EMR platforms delivered via the internet.
Re: (Score:2)
Expect the prices of these things to soar as their liability insurance costs far outweigh their costs of production and advertising.
I worked for a pacemaker company in the 90's. The potential cost of litigation was enormous. Particularly in the light that literally every customer was trying to die from the condition that necessitated the product purchase in the first place.
Stupid U.S. tort law dramatically ran up the costs. For example, if a device failed because of bad software and the pacemaker company went bankrupt, every company involved with the manufacture is liable. So in this case, Dow Chemical might have supplied a gasket or s
Re: (Score:3)
Expect the prices of these things to soar as their liability insurance costs far outweigh their costs of production and advertising.
I worked for a pacemaker company in the 90's. The potential cost of litigation was enormous. Particularly in the light that literally every customer was trying to die from the condition that necessitated the product purchase in the first place.
Stupid U.S. tort law dramatically ran up the costs. For example, if a device failed because of bad software and the pacemaker company went bankrupt, every company involved with the manufacture is liable. So in this case, Dow Chemical might have supplied a gasket or something. Plaintiffs can go after Dow even though everyone agrees that they had no contribution to the failure. Because of that idiocy every vendor related to the device charges astronomical prices for any component.
Complex laws/regulations plus the insurance and litigation scams must hurt the US economy so badly. Healthcare in the US is more expensive than anywhere else in the developed world and yet Americans get so little for their money, life expectancy around the lowest in the developed world; the people who profit most are the lawyers and insurers and they are absolutely milking the American people.
The same applies in pretty much every field of endeavor in North America; liability insurance, various other kinds o
Accuracy of other heart rate monitors? (Score:2)
How does the FitBits' accuracy compare with the many other consumer-grade heart rate monitors on the market? e.g. The ones with a strap you wear around your chest.
If the FitBits do a bad job of measuring heart rate - to the point of being worthless noise - then I agree they ought to be sued for selling a product that doesn't do what it advertises. But I'd like to see a less biased party - such as a fitness magazine, or Consumer Reports - do the testing rather than a lawyer chasing a paycheck.
Re: (Score:2)
Here's a review [dcrainmaker.com] from a reviewer I trust. Compared to heart rate straps, wrist based HRMs seem to be not very good at tracking heart rate during intense workouts. It also seems like it has trouble tracking changes that occur quickly during such as during interval training.
Garmin saw it coming (Score:4, Interesting)
I was wondering why Garmin (FitBit competitor) was proeminently displaying the disclaimer below on their Web site.
Now I know why..
Activity Tracking Accuracy
Garmin activity trackers are intended to be tools to provide you with information to encourage an active and healthy lifestyle. Garmin activity trackers rely on sensors that track your movement and other metrics. The data and information provided by these devices is intended to be a close estimation of your activity and metrics tracked, but may not be completely accurate, including step, sleep, distance, heart rate and calorie data. Garmin activity trackers are not medical devices, and the data provided by them is not intended to be utilized for medical purposes and is not intended to diagnose, treat, cure, or prevent any disease. Garmin recommends you consult your doctor before engaging in any exercise routine.
Accuracy of Wrist-based Heart Rate (Elevate)
The optical wrist heart rate (HR) monitor for Garmin wearables is a valuable tool that can provide an accurate estimation of the user’s heart rate at any given point in time. The optical HR monitor is designed to attempt to monitor a user’s heart rate 24 hours a day, 7 days a week. The frequency at which heart rate is measured varies, and depends on the level of activity of the user. When you start an activity with your Garmin optical HR device, the optical HR monitor provides feedback more frequently as the optical sensor is on all of the time and is trying to measure heart rate on a continuous basis during a given activity period. The intent is to provide the user with a more frequent and accurate heart rate reading during a given activity.
While our wrist HR monitor technology is state of the art, there are inherent limitations with the technology that may cause some of the heart rate readings to be inaccurate under certain circumstances. These circumstances include the user’s physical characteristics, the fit of the device and the type and intensity of the activity as outlined above. The HR monitor data is not intended to be used for medical purposes, nor is it intended to diagnose, treat, cure or prevent any disease or condition.
Re: (Score:2)
Garmin has been doing fitness tracking for a very long time now so it's not surprising they have all their bases covered. Their watches are among the best and put FitBit's offerings to shame. Not that I think this lawsuit has any merit though; unless FitBit actually advertises their watches as flawless health trackers.
Regardless of the device, measurements are not always going to be exact because of a variety of factors and HR monitors are notoriously finicky.
Re: (Score:2)
accurate estimation
Hahaha. The fine art of marketing without actually committing to anything.
Pity they won't accept cash that is an accurate estimation of the sales price.
Re: (Score:2)
Pity they won't accept cash that is an accurate estimation of the sales price.
If it is THEIR estimation, I'm sure they won't have a problem with it.
Consumer Reports Tested and Found Opposite (Score:3, Informative)
http://www.consumerreports.org... [consumerreports.org]
The new testing confirmed our earlier results: Both the Charge HR and Surge were very accurate when compared to the reference Polar H7 ECG monitor. During nearly every trial, the variance between the chest strap and the Fitbit devices amounted to no more than three heartbeats per minute.
However, there was one exception: When our female tester wore the Fitbit Charge HR on her wrist and got up to higher intensity levels, the margin of error crept upwards. During one run, when the chest strap read 150 bpm, the Fitbit Charge HR read 144 bpm. During the second run, the device read only 139 bpm. That problem went away when she wore the Charge HR on her forearm. (And the Fitbit Surge was accurate no matter how it was worn.)
Re: (Score:2)
It's gotten to the point that manufacturers will have to find a way to FORCE people to read the instructions before allowing them to use their products.
Of course, it would help if they actually still provided full manuals in the box instead of making consumers find them on the internet.
This One's Pretty Good (Score:3)
I'm sure there's plenty of caveat emptor to go around, but the very first thing I did when I got my Charge HR was to test it by taking my pulse myself and comparing it to the fitbit number.
The resting heart rate is dead on. (not their calculated resting heart rate--that's a dumb, arbitrary number they come up with, but the real time resting heart rate is accurate.)
I've had a few troubles with the workout heart rate, but not because it can't count, but because the wristband moves around after sweat dislodges it. It can slip down my wrist and the sensor will lose contact with my skin. But when that doesn't happen, the number is pretty close.
For a while at first, I wore my under armor heart rate monitor on my chest along with the fitbit, and they were pretty much in sync, too.
This lawsuit is why we can't have nice things.
Re: (Score:2)
Re: (Score:2)
But if the premise is, "they're not accurate" - a data point of one does show that the statement is false.
It's very hard to prove something true, yet all it takes is one counterexample to prove a claim false, which is what I am providing.
Define heart rate. (Score:3)
Seems easy to do, doesn't it? You take the reciprocal of the interval between heartbeats scale that to beats per minute and there you go.
Except if you've ever designed software and had to look at a problem like this, you'll understand that it's not nearly so simple. The heart isn't nearly precise as the quartz oscillator you're using for your timing reference. Sometimes it throws in an early beat or late one, because it's an electro-chemo-mechanical oscillator that works by the flow of ions across a membranes of countless cells. So the rate is going to jump around a little bit second to second, which will only confuse the user. What's more any sensor that isn't stuck on with adhesive is going to miss a few signals now and then, or maybe get a spurious one.
So what you do is take a moving average to smooth out all the kinds of noise you have in your signal. Having a fitbit myself, I find it surprisingly accurate when compared against a manual pulse when your heart rate is steady. Watching the figures as I exercise hard, it's clear there's a lag in response as your heart rate accelerates in particular (since the heart slows this is less of a problem as you slow down), which indicates that the device is giving me some kind of moving average.
And it's OK. The point is to give users useful feedback about how their heart is doing during periods of strenuous exercise, not to give them a beat by beat accounting of what the sensors are picking up. It doesn't have to be laboratory-precise or instantaneous because there's nothing useful users can do with that precision. I've lost count of many times have I had to explain these two things to clients: you don't need feedback that's an order of magnitude faster than you're capable of responding too, and you shouldn't take action based on statistical noise; data doesn't have to be perfectly precise, they just have to tell you whether you're in the right ballpark or headed in the right direction.
The fitbit works very well for the purpose it's intended and the way users use it. You take a series of readings (which are sometimes off, but recognizably so) to establish what your heart is doing, and then shift to a new level of effort and take several readings as your heart settles into a new equilibrium.
Anyhow, note the weasel phrase "Up to 20 beats per minute." This means in all their testing the very worst discrepancy they ever found between the readings taken from glued on electrodes from the loosely cinched bracelet monitor was 20 beats per minute. That actually sounds pretty good to me for a worst case result.
Re: (Score:2)
Medically, heart rate always involves averaging many beats, usually by counting beats over a time interval.
"Up to" (Score:3, Interesting)
"miscalculated heart rates by up to 20 beats per minute"
"Up to" -- like "as much as" -- is a marketing phrase, not a description of results. I haven't read the study -- I didn't see any useful information in the linked NBC News article as to how to find it.
Re: (Score:2)
(grabs Soda, popcorn and a big box of candy)
Re: (Score:2)
"miscalculated heart rates by up to 20 beats per minute"
"Up to" -- like "as much as" -- is a marketing phrase, not a description of results. I haven't read the study -- I didn't see any useful information in the linked NBC News article as to how to find it.
I always like it when you read that something came in the top 7 (or any other random number). So it came 7th then.
Re: (Score:2)
Re: (Score:2)
This is really stupid. Fitbit has never claimed that their products were ECGs. The heart rate is an estimate, and the estimate can be greatly impacted based on a large number of factors. It's a freakin' optical sensor. Everything from dried sweat to lose bands to body hair can interfere with the measurement.
They're activity trackers. They're supposed to help track your general activities across over the course of a day, not give you a detailed medical diagnostic on your heart rate. They're an estimation too
Mo money mo money (Score:2)
and nothing more than an attempt to extract a payout from Fitbit.
This is an accurate statement, even if the watch has problems.
It's still a great device for the main purpose (Score:2, Offtopic)
Re: (Score:2)
Re: (Score:2)
Exactly how has this harmed anyone? (Score:3)
Exactly how has this harmed anyone?
Everyone knows pedometers aren't accurate. This is just a continuation of what we all knew in the 1980s and 1990s.
I don't see how this lawsuit has any merit whatsoever. Whom has it harmed, and how?
What about all the other pedometers, like the ones health insurance companies issue to employees with which points are earned to obtain discounts?
I thought it was well known (Score:2)
Good to see some actual studies done on this, but I think that many people who work out already knew about this. Here's a review [dcrainmaker.com] of the Fitbit Charge HR which shows that during periods of intense exercise, that the fitbit doesn't track very well. It seems to do a pretty good job when you aren't exercising, but compared even to a heart rate strap worn on the chest, the accuracy is lacking.
Common sense (Score:2)
Of course it's not very accurate! (Score:2)
Re: (Score:2)
Fitbit devices don't use electrical signals to measure your heartbeat. They work optically by sensing blood flow under the skin.
Consumer Reports test of accuracy (Score:2)
Re: (Score:2)
FitBit's documentation [fitbit.com] says to place it higher than the protuberance.
ruining it for those of us with common sense (Score:2)
I have a similar (non-fitbit) watch I use for running. I like it. I understand it's not 100% accurate. It's accurate enough for its cost, and I'm happy with that. If lawsuits like this continue to fly, such products will get more expensive, or harder to find.
I have yet to see an accurate wrist heart monitor (Score:2)
I think people have false expectations of what these things can do. Fitbit, Apple and all these companies are well advised to set expectations properly.
That said, I'm glad to have it even if its not completely accurate. I use it as a guide and motivational tool. I use my phone as a flashlight sometimes. Its not a great flashlight, but its handy when I need one. Same thing
consider normal variation in pulse rate (Score:2)
I'm not here to defend health gadgets but to condemn the impression that traditional measuring devices are accurate. According to TFS "Subjects were then hooked up ... "--in other words there was a sequence where the gadget was used and later a supposedly accurate device was compared. A simultaneous comparison might have been valid but sequential is questionable.
I test myself about five times every morning over a roughly ten minute period. Each reading is different, often significantly. Not just heart rate,
What did they expect FitBit to respond with? (Score:1)
Not even slightly surprising (Score:2)
The early fitbits were basically a computer connected pedometer for goodness sakes (!) yet they charged $100 for it. /accurately/ measures heart rate, altitude, gps coordinates, ambient temperature and steps (if even possible??) could probably give semi-reasonable estimations on health benefits or calories burned but even a highly accurate device wouldn't be perfect. However the consumer stuff fitbit shovel out is weak at beast.
I am sure a device which
plaintiffs study of Fitbit accuracy (Score:1)
Matches my experience (Score:1)
At least they got numbers... (Score:2)
... Most of the time when I'm exercising I can't get a number out of mine.