Abstract
Utilizing the triangulation principle of general surveying methods we developed a system for measuring the spatial position of solid objects with 3D co-ordinates and investigated its reliability and validity. For the reliability, we assessed measurement of a plastic triangle by 10 examiners. The validity was assessed by comparison with a 3D motion analysis system. The examiners' intraclass correlation coefficient was 0.97, and their intraclass correlation coefficient for three repeated measurements was 0.93. The measurement error in camparison with the 3D motion analysis system was within 1 mm. By these results, we consider the validity and reliability of the spatial position measuring system was demonstrated, and we think it can be used effectively, especially as a local motion analyzer.
