Objectives: To examine the prevalence of mobility device use in community‐dwelling older adults in the United States and to investigate the incidence of falls and worry about falling according to type and number of mobility devices used. Design: Analysis of cross‐sectional and longitudinal data from the 2011–12 National Health and Aging Trends Study. Setting: In‐person interviews in the homes of study participants. Participants: Nationally representative sample of Medicare beneficiaries (n = 7,609). Measurements: Participants were asked about mobility device use (e.g., canes, walkers, wheelchairs and scooters) in the last month, 1‐year fall history and worry about falling. Results: Twenty‐four percent of adults aged 65 and older reported mobility device use in 2011, and 9.3% reported using multiple devices within the last month. Mobility device use increased with advancing age and was associated with nonwhite race and ethnicity, female sex, lower education level, greater multimorbidity, and obesity (all P < .001). Adjusting for demographic and health characteristics and physical function, the incidence of falls and recurrent falls was not associated with the use of multiple devices or any particular type of mobility device. Activity‐limiting worry about falling was significantly higher in cane‐only users than in nonusers. Conclusion: The percentage of older adults reporting mobility device use is higher than results from previous national surveys, and multiple device use is common in those who use any device. Mobility device use is not associated with greater incidence of falls. Cane‐only users may compensate for worry about falling by limiting activity.

Objectives: The aim of this study was to evaluate the accuracy of three consumer-based activity monitors, Fitbit Charge 2, Fitbit Alta, and the Apple Watch 2, all worn on the wrist, in estimating step counts, moderate-to-vigorous minutes (MVPA), and heart rate in a free-living setting. Methods: Forty-eight participants (31 females, 17 males; ages 18–59) were asked to wear the three consumer-based monitors mentioned above on the wrist, concurrently with a Yamax pedometer as the criterion for step count, an ActiGraph GT3X+ (ActiGraph) for MVPA, and a Polar H7 chest strap for heart rate. Participants wore the monitors for a 24-hour free-living condition without changing their usual active routine. MVPA was calculated in bouts of ≥10 minutes. Pearson correlation, mean absolute percent error (MAPE), and equivalence testing were used to evaluate the measurement agreement. Results: The average step counts recorded for each device were as follows: 11,734 (Charge2), 11,922 (Alta), 11,550 (Apple2), and 10,906 (Yamax). The correlations in steps for the above monitors ranged from 0.84 to 0.95 and MAPE ranged from 17.1% to 35.5%. For MVPA minutes, the average were 76.3 (Charge2), 63.3 (Alta), 49.5 (Apple2), and 47.8 (ActiGraph) minutes accumulated in bouts of 10 or greater minutes. The correlation from MVPA estimation for above monitors were 0.77, 0.91, and 0.66. MAPE from MVPA estimation ranged from 44.7% to 55.4% compared to ActiGraph. For heart rate, correlation for Charge2 and Apple2 was higher for sedentary behavior and lower for MVPA. The MAPE ranged from 4% to 16%. Conclusion: All three consumer monitors estimated step counts fairly accurately, and both the Charge2 and Apple2 reported reasonable heart rate estimation. However, all monitors substantially underestimated MVPA in free-living settings.