Influence of Camera Location on the Accuracy of Visual Estimation of Body Segment

다국어 초록 (Multilingual Abstract)

Objective: The aim of this study is to investigate the influence of camera location on the accuracy of visual estimation (VE) of body segments. Background: Various ergonomic methods have been used to investigate the work-related musculoskeletal disorder factors. The VE method is regard as valid and reliable comparing to the self-report and direct method. The previous VE study is limited by choosing the observational direction. Method: Eight body segments at fullrange of motion (ROM) were presented by a volunteer, the ROMs at each 10º were measured by goniometer and captured from 5 camera locations. Thirty observers visually estimated the segment angles displayed on the digital images. The average absolute error respect to the goniometric measurement was calculated to assess the VE accuracy. Results: For the whole body, the camera location significantly (P<0.0001) affected the VE accuracy, the 135 and 90 degree camera location exposed the lowest error. Hand estimation and foot estimation showed the highest (14.0±11.7º) and lowest (9.0±8.0º) estimation error. Conclusion: The 135 degree camera location is the optimal direction to capture and visually estimate body postures in the laboratory. Application: This study would contribute to the direction determination when applying VE in the field, furthermore to provide the correlated data to assess the bias in epidemiological studies.

목차 (Table of Contents)

• ABSTRACT
• 1. Introduction
• 2. Method
• 3. Results
• 4. Discussion
• Reference
• Author listings