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How did they track the steps of people "without" a pedometer or other tracker is what I want to know.


> At the start of the study, the team asked all 90 participants’ permission to pull information generally from their phones, without telling them that their step counts from the weeks prior were being recorded. This provided the elusive baseline measure of how much participants walked when they weren’t being actively monitored




The measurement remains on the phone that both the experimental and control groups carry. The variable is the experimental group gets a secondary step counter. What the step counter reads is irrelevant. This accounts for the randomness of setting the phone down throughout the day.


The operative word being "elusive". This will only provide distance while carrying the phone ...


That is pretty much all day for most people


But that time they aren’t carrying their phone could easily be 318 steps worth of time vs those who had a watch on there wrist for definitely all day. I would assume carting their phone all the time would be a requirement for the study though, I’d hope.


They took the step measurments from the participant's phones in both groups, they didn't just use the phone measurements for the control group and just use the tracker's measurements for the other. So the 318 steps worth definitely demonstrates a real increase in steps fom the experimental group, even if the number itself might not be accurate.


They obviously weren't comparing steps measured from watches with phones.


I had exactly this thought. I sometimes walk 1000 or more steps on my watch that my phone doesn't track because I leave my phone on my desk or charger as needed instead of carrying it around the house while I do chores and things.


Yup, my phone stays on my desk most of the time I'm at home, as I use a bluetooth headset while I'm working that has a great range. I often leave it on in the evening too as it's comfortable and I'm already listening to music on it when I stop working. So, my phone wouldn't record any steps, where my pedometer would record all of them. So, around 300 extra per day for me too.




While that makes the numbers less accurate, the bias is the same.


Did they use phone data or pedometer data for pedometer wearers?


Don't all modern smart phones have a pedometer / health core function?


Yep, that's how they measured step count, form phones.


Maybe it’s that, on average, people who are more active in general are more likely to buy a fitness tracker? It may not be that wearing one makes you walk more.


That may well be true, but in this study the researchers randomly selected some of the 90 participants and gave them pedometers. So it wasn't self selecting.




Did they control for measurement inaccuracies?


I certainly don’t agree with the claim that the experiment design was “ingenious”. It’s also only two weeks and not a long-term study - just because someone flosses their teeth in the few days running up to a dental appointment doesn’t mean they will the rest of the year. Similarly, if you give someone a pedometer as part of a study, you’ll definitely see some change in behaviour in the short-term and that’s all they’ve shown here.


The study was two weeks long. I wonder how much of the difference in steps evens out over time. I suspect the average steps even out after 2 months.


I think that's cause they don't track accurately enough. I work at a desk and only typically walk to the bathrooms and such, to my car and back. Despite that my smart watch reports I walk around 4k steps a day, with zero chance I actually did. It tracks vibrations or arm movements as steps, so when you drive, move your hands around a workspace, or even just adjust your glasses it can count a step. Not always, but from what I've seen so far it happens pretty regularly.


You get what you track. Even if you don’t track it.


Oh yeah? I wonder who funded that ‘research’.


Kinda self selecting demographic though. Fitter people are more curious about their steps.


They randomly gave the pedometers to the some of the group of 90 in the study. So self selecting can be true, but it can also be true that giving people a pedometer they may not have purchased themselves, like an employer doing so, can have an effect on steps.


How do they know this when the pedometer wasn't on the people who didn't have a pedometer?


They used smartphone data. Participants were asked to download a smartphone app. The participants were told it was tracking their 'activity', but they were vague about what was included in 'activity'. The group was then split into three cohorts: one was given a pedometer; one was given a pedometer and told to record their results; one was not given a pedometer and was not told to record their results. Those given pedometers walked modestly more than those who were not.


79% of all statistics are made up!