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How much can we demand of consumer connected health?

May 2, 2014

A few years back, when I first became fascinated by self-tracking, I committed to use and understand all of the trackers on the market at the time.  It would be hard to make that kind of commitment today as the field has widened dramatically. But in 2009, it was much more confined. I had a BodyMedia armband, a Withings scale and a FitLinxx ActiPed pedometer.  One thing I learned early on was that their readings don’t always hang together well.

For instance, we know that much of daily weight fluctuation is about salt intake and fluid retention, and the body composition function on the Withings scale has trouble with that.  Here are two real readings from me on recent successive days:  weight 186.6, fat mass 25.59, then 184.6 and 24.03.  Logic would dictate that if I lost 2 lbs in one day it would have to be water weight and my body fat composition should go up not down.

I had the same early consternation with the BodyMedia armband and the ActiPed.  FitLinxx is on the record as saying their technology measures steps most accurately. BodyMedia uses a proprietary algorithm that includes a number of inputs.  My personal data recorded on these two devices were routinely different.  When Fitbit came out, I say that device gave a different number still.

It gets even more peculiar when you use MyFitnessPal to count calories in and try to map the calories/calories out (based on an activity monitor) with the weight readings from Withings.

You get the picture.  Quantified selfers, like me, are asking too much of these simple technologies.

What I learned over time is that these tracking devices are directionally correct.  They are most helpful when the data from each sensor is viewed longitudinally, in its own context.  For a time I wore both a Jawbone UP and a Fitbit and I found that though the step counts registered were quite different on each activity tracker, the percentage variability of each from day to day was pretty consistent. In my experience, they are internally consistent.

Acitivity trackers_Wellocracy_cHealth blog kvedar

This is all background to comment on an article by Nick Bilton that was featured in this past Monday’s New York Times, entitled:  For Fitness Bands, Slick Marketing but Suspect Results.  In this article, Bilton makes the case that activity trackers are really inaccurate.  He mentions personal experiences where he and a friend were both wearing the same monitor, at the same time doing the same thing, and got wildly different results. He also reported another incident when he was using his smartphone’s GPS tracker to measure his activity and, though he was sedentary, it showed him to have been active.

First off, I have not reproduced experiences like either of these.  However, it’s worth noting that the technologies are nowhere near perfect.  The standard technology to measure activity is an accelerometer and it is only as good as the software algorithm guiding it.  Almost all activity trackers know when you are driving a car or riding a bike and don’t count that.  However, bouncing your leg up and down while at rest or swinging your arm back and forth can yield false positive results.

Sleep trackers are even worse.  Since they track sleep indirectly by measuring activity, they are all over the map.

Expecting these consumer devices to have scientific accuracy is unrealistic.  Expecting them to help you keep your activity level top of mind and measured in context from day to day is realistic and in most cases helpful.

Our experience using activity monitoring in programs at the Center for Connected Health has demonstrated this.  The objective feedback is helpful in setting a tone for the individual and as a data stream to guide motivational tools such as automated coaching.

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For example, one of our physicians at Mass General Hospital gave nine of her patients with diabetes a Fitbit Zip  and met with them, as a group, weekly.  After six weeks, nearly 80% of these 60 plus year old patients increased their amount of weekly exercise, in particular walking, and 22% lost a significant amount of weight, with one patient losing over 10 lbs.  More than half of these patients are still using their Fitbits, eight months after the program was completed, and all reported that they felt more confident in their ability to care for themselves, and everyone was moving more.

We never expected consumer devices to be as accurate as laboratory calculations of activity level or calories burned.

One of the reasons we launched Wellocracy was to help consumers understand nuances like this.  So far it’s been a great success.

Does it matter if every step is counted, every calorie recorded, or is it more important that these personal health technologies are making us more aware, more motivated and more likely to make healthier lifestyle choices?

13 Comments leave one →
  1. Peter L. Albrecht permalink
    May 3, 2014 3:45 pm

    Gadgets can be great fun. I love them. But, taking the case of your MGH colleague and her group of diabetic patients, isn’t the issue not how accurately a given gadget can record one’s caloric intake, output, weight, fat percentage and the like, but rather, how can you motivate those patients to move? I’d bet that the weekly meetings had a good deal more to do with the group’s success than the gadget. By the same token, I’d bet that you didn’t vary your exercise routine simply because you had a gadget on your wrist. If they can help making exercise – like health – addictive, great. But I think a supportive group would be much more effective. As a confirmed 80-year-old addict, I couldn’t care less about calories, heart rate, fat percentage, or any other statistic. But the enthusiasm of my fellow spinners, step-aerobicers, lifters and Pilates addicts goads me to show up for a class whenever I’m tempted to slack off.

  2. May 3, 2014 4:25 pm

    They work together (gadgets and motivation). Each is less effective without the other. The data from the gadgets gives the opportunity for setting, measuring and achieving goals, for managed competition, for accountability. Without the objective data, we all report aspirational results, rather than accurate ones.

    • Peter L. Albrecht permalink
      May 4, 2014 3:11 pm

      Yep! I wasn’t aware of the tendency to report “aspirational results, and I can see how a gadget, even if not terribly accurate, would be very helpful in counteracting that tendency.

  3. May 12, 2014 1:17 pm

    How timely! I purchased a FitBit today in hopes it will help be my conscience to exercise during the day. I also hope that my 3 other friends with FitBits and My Fitness Pal accounts will be my support group. The benefit to gadgets right now may be more behavioral than scientific but as long as I can set a goal and see if I am meeting a goal, that’s all I will expect for $99.

  4. May 12, 2014 3:01 pm

    As long as you remain goal oriented, it should work!

  5. May 12, 2014 9:04 pm

    What is taxing my mind, and that of my company, at the moment is how tracking can not just motivate but help, over time, to illuminate personalised models of behaviour change. By this I mean, looking at our own longitudinal data to see patterns. For example, I believe that i have cycles of high engagement with my health through diet, exercise and alcohol but I have never correlated those with working hours, levels of happiness/stress, relationships, etc. If we can identify patterns rather than trends and build ‘alerts’ plus support groups around those (digital or otherwise) we may have the ability to make beneficial change in our health behaviors by overcoming patterns (in a gestalt type way) rather than just tracking trends?

    • Peter L. Albrecht permalink
      May 13, 2014 12:08 pm

      I think this is an extremely important contribution. It’s so easy to isolate this factor or that (e.g., blood pressure, heart rate) from the larger context (Jen’s example of happiness/stress) and from such finer points as “good stress” (a good game of tennis or bridge) from “harmfull stress” (fear of change, loss). Maybe some patterns don’t need to be overcome so much as modified a bit. And just looking at a pattern, recognizing its existence, observing it for a while, creates a mental and emotional space in which one can make changes in the pattern.

  6. May 12, 2014 10:11 pm

    You’ve stated it perfectly!

  7. May 29, 2014 5:17 pm

    Overheard at Stanford Medicine X a couple of years ago: “Why do we think self-tracking health devices will work when mirrors and bathroom scales have so far failed?”

  8. May 29, 2014 6:07 pm

    In my time with Continua and IEEE I regularly got frustrated with the tech guys obsessing about the accuracy of the data. The data indicates a direction and a result – so it matters most that my measuring is consistent so I can compare, not about accuracy as an absolute.

    The numbers are never going to be an absolute. So if I have a BMI of 27 versus 24, how many months longer might I live? Nobody knows. And how well might I live?

    People who follow their metrics via something like Fitbit know that it makes sense. They do a bit more every day that they otherwise might and they know they feel better for being that much fitter. Measuring makes sense but then you should be confident that the measurements are consistent.

    The headline question here was about what we can demand of consumer connected health. For me this not only involves living optimally, it also involves accepting death as an inevitability. Sooner or later those metrics will be on the decrease and this too is natural and should perhaps be welcomed…. The way we choose to live the life we have is what connected health can help us realise.


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