Reliability and concurrent validity of a mobile application to measure thoracolumbar range of motion in low back pain patients

BACKGROUND: Smartphone devices have been used to measure range of motion (ROM) in different joints. OBJECTIVE: To verify the concurrent validity of thoracolumbar ROM using a mobile application and a digital inclinometer, as well as the intrarater reliability of individuals with and without back pain. METHODS: One investigator was responsible for measuring the ROM during the evaluations performed on 20 asymptomatic subjects and 20 symptomatic subjects in two consecutive days. RESULTS: Regarding to the concurrent validity, the Intraclass Correlation Coefficients (ICC) were classified as very good for all analyzed movements. For intrarater reliability, the mobile application had ICC varying between good and very good for the symptomatic subjects and very good for asymptomatic subjects. CONCLUSIONS: The mobile application may be considered a valid and reliable tool to assess thoracolumbar ROM for both asymptomatic and chronic low back pain subjects.