Validity of a smartphone-based assessment of spatiotemporal gait parameters and center of mass displacement during single- and dual-task walking

Abstract

                Background: Development of new techniques to assess gait in the free-living environment is necessary.  Nowadays, the use of smartphone technology for medical purposes is becoming popular due to its cost-effectiveness, portability, and variety of built-in sensors.

                Objectives: To assess the validity of a smartphone-based accelerometer to measure spatiotemporal gait parameters and center of mass (CoM) displacement during single- and dual-task walking, compared with a motion capture system.

                Methods: Twenty-four healthy young and older adults were asked to walk at their self-selected speed over a 10-m walkway under single-task normal walking and four dual-task walking conditions. To evaluate validity, gait parameters (i.e. step time, step length, gait velocity, cadence, and CoM displacement) derived from a smartphone and a motion capture system were analyzed using Pearson Correlation Coefficient (r).

                Results: A smartphone-based accelerometer demonstrated high to very high concurrent validity with a motion capture system for all spatiotemporal gait parameters during single-task walking (r = 0.789 - 0.990, p < 0.001) and dual-task walking (r = 0.789 811 - 0.990, p < 0.001). For vertical CoM displacement, a smartphone-based accelerometer demonstrated moderate (r = 0.563, p < 0.001) and moderate to high (r = 0.588 - 0.745, p < 0.001) correlations during single - and dual-task walking, respectively. 

                Conclusion: The smartphone-based accelerometer is valid for the quantification of gait during both single- and dual-task walking. Thus, there is a great potential of using a smartphone to assess gait in the clinic and community.