Reliability and criterion validity of an iPhone® application with a caliper for quantifying trunk rotation passive range of motion
2022 Volume 8 Issue 1 Pages 49-56
Details
2022 Volume 8 Issue 1 Pages 49-56
BACKGROUND: Reliable and objective methods to measure trunk rotation are not well-established; therefore, simple clinical measures to quantify trunk rotation need to be developed.
OBJECTIVES: In this study, two methods were compared to measure the passive range of motion (ROM) of trunk rotation. The reliability and validity of an iPhone® application with a caliper were compared with those of three-dimensional motion analysis (3DMA).
METHODS: Passive ROM of trunk rotation was measured in 15 healthy male individuals. Intra- and inter-rater reliabilities were determined by calculating the intraclass correlation coefficients (ICCs). The iPhone® application with a caliper was validated against 3DMA using Pearson’s correlation coefficient, and agreement levels were identified using Bland-Altman plots and 95% limits of agreement.
RESULTS: The iPhone® application demonstrated moderate-to-good intra-rater (ICC=0.73) and excellent inter-rater reliability (ICC=0.75). A strong and significant correlation was found between measurements obtained using 3DMA and the iPhone® application with concurrent validity (r=0.87, p<0.01). However, the 3DMA measurements were consistently higher than the iPhone® application measurements (mean difference 4.74°, p<0.01), and the upper and lower limits of agreement were 11.14° and −1.67°, respectively.
CONCLUSIONS: These results indicate that the iPhone® application with a caliper can be used to assess passive ROM of trunk rotation.
