Below is a post from Joseph Agu's Facebook page.
His page can be found here: Joseph Agu ENC.
How Accurate are Activity Trackers?
In a study published a few months ago, Chowdhury and colleagues compared the daily energy expenditure estimates from consumer multi-sensor activity monitors.
To do this, the researchers had a group of 30 men and women wear the different trackers in free living conditions and compared the data to that produced by a criterion method (the Actiheart).
As you can see from the chart, there was a negative bias for mean daily energy expenditure estimates from these four commercially available devices. In other words, they underestimated actual daily energy expenditure, with the Apple Watch and the Fitbit Charge HR being the better options, compared to the Microsoft Band and the Jawbone UP24.
The authors reasonably conclude that “Some consumer multi-sensor devices such as the Apple Watch and Fitbit Charge HR provided reasonably good estimates of energy expenditure both in the laboratory and during free-living conditions. However, this was not the case across all devices and certainly these consumer monitors do not all produce similar results (i.e., they are not equivalent). It is also clear that devices with more sensors do not necessarily produce better energy expenditure estimates than simple previous-generation accelerometry-only devices. We propose that independent quality standards should be developed to verify claims regarding energy expenditure estimation from consumer wearables or manufacturers should be required to provide accuracy ‘ratings’ at the time of going to market.”
FREE full-text link to the paper - https://goo.gl/yY79XH