FREE-LIVING VALIDATION AND HARMONIZATION OF 10 WEARABLE STEP-COUNT MONITORS: 639. (August 2021) - Park, Susan; Marcotte, Robert T.; Toth, Lindsay P.; Paulus, Paige; Lauricella, Lindsey; Kim, Andrew H.; Crouter, Scott E.; Springer, Cary M.; Staudenmayer, John W.; Bassett, David R.