Accuracy of 2 activity monitors in detecting steps in people with stroke and traumatic brain injury

I am planning on getting a Fitbit because I need to walk more, lose weight.
A cheapo pedometer I had did not measure steps with any amount of accuracy.
http://search.naric.com/research/rehab/redesign_record.cfm?search=2&type=all&criteria=J68103&phrase=no&rec=124281
NARIC Accession Number: J68103.  What's this?
ISSN: 0031-9023.
Author(s): Fulk, George D.; Combs, Stephanie A.; Danks, Kelly A.; Nirider, Coby D.; Raja, Bhavana; Reisman, Darcy S..
Publication Year: 2014.
Number of Pages: 8.
Abstract: Study examined the accuracy of 2 consumer/patient activity monitors, the Fitbit Ultra and the Nike+ Fuelband, in identifying stepping activity in people with stroke and traumatic brain injury (TBI). The study also compared the accuracy of these 2 activity monitors with that of the StepWatch Activity Monitor (SAM) and a pedometer, the Yamax Digi-Walker SW-701 pedometer (YDWP). Thirty people with chronic stroke and 20 with TBI wore the 4 activity monitors while performing the Two-Minute Walk Test, during which they were videotaped. Activity monitor estimated steps taken were compared with actual steps taken counted from videotape. Accuracy and agreement between activity monitor estimated steps and actual steps were examined using intraclass correlation coefficients (ICC) and the Bland-Altman method. The SAM demonstrated the greatest accuracy (ICC = .97, mean difference between actual steps and SAM estimated steps = 4.7 steps) followed by the Fitbit Ultra (ICC = .73, mean difference between actual steps and Fitbit Ultra estimated steps = 9.7 steps), the YDWP (ICC = .42, mean difference between actual steps and YDWP estimated steps = 28.8 steps), and the Nike+ Fuelband (ICC = .20, mean difference between actual steps and Nike+ Fuelband estimated steps = 66.2 steps). Findings suggest that the Fitbit Ultra may be a low-cost alternative to measure the stepping activity in level, predictable environments of people with stroke and TBI who can walk at speeds of at least 0.58 meters per second.