Reliability and Validity of Observational Gait Analysis by Physical Therapists: Possibility of Verifying Accuracy and Improving Technology in Visual Measurement of Joint Angles

Although intra-rater reliability tended to be higher than inter-rater reliability, neither reached levels considered sufficiently reliable, and validity showed only limited agreement with reference values. These results highlight the limitations of visual estimation in joint angle assessment. Future efforts should focus not only on improving observational consistency but also on improving agreement with reference values through corrective training using still images.