An Experimental Study on the Validity and Reliability of a Smartphone Application to Acquire Temporal Variables during the Single Sit-to-Stand Test with Older Adults

• Published in: Sensors (Basel, Switzerland) Switzerland), 2021-03, Vol.21 (6), p.2050
• Main Authors: Marques, Diogo Luís, Neiva, Henrique Pereira, Pires, Ivan Miguel, Zdravevski, Eftim, Mihajlov, Martin, Garcia, Nuno M, Ruiz-Cárdenas, Juan Diego, Marinho, Daniel Almeida, Marques, Mário Cardoso
• Format: Article
• Language: English
• Subjects: accelerometer sensor; Accelerometers; Acoustic emission testing; Adults; Aged; aging; Coefficient of variation; Correlation analysis; Correlation coefficients; Data acquisition; Error analysis; Female; Frailty; Human error; Humans; Institutionalization; Kinematics; Male; mobile application; Mobile Applications; Mobile communications networks; Mobility; Older people; Reliability analysis; Reproducibility of Results; Sensors; Smartphone; Smartphones; stand-up time; Standard error; total time; Validity; Womens health
• ISSN: 1424-8220; 1424-8220
• DOI: 10.3390/s21062050

Smartphone sensors have often been proposed as pervasive measurement systems to assess mobility in older adults due to their ease of use and low-cost. This study analyzes a smartphone-based application's validity and reliability to quantify temporal variables during the single sit-to-stand test with institutionalized older adults. Forty older adults (20 women and 20 men; 78.9 ± 8.6 years) volunteered to participate in this study. All participants performed the single sit-to-stand test. Each sit-to-stand repetition was performed after an acoustic signal was emitted by the smartphone app. All data were acquired simultaneously with a smartphone and a digital video camera. The measured temporal variables were stand-up time and total time. The relative reliability and systematic bias inter-device were assessed using the intraclass correlation coefficient (ICC) and Bland-Altman plots. In contrast, absolute reliability was assessed using the standard error of measurement and coefficient of variation (CV). Inter-device concurrent validity was assessed through correlation analysis. The absolute percent error (APE) and the accuracy were also calculated. The results showed excellent reliability (ICC = 0.92-0.97; CV = 1.85-3.03) and very strong relationships inter-devices for the stand-up time ( = 0.94) and the total time ( = 0.98). The APE was lower than 6%, and the accuracy was higher than 94%. Based on our data, the findings suggest that the smartphone application is valid and reliable to collect the stand-up time and total time during the single sit-to-stand test with older adults.