Inter Rater Reliability Study in Placing Anatomical Markers for Photogrammetric Postural Assessment

Abstract

Objective: To verify the inter rater reliability when placing skin markers on 33 anatomical points. Material and Methods: the sample consisted of 2 groups: the raters group (GE) with 3 trained physiotherapists and the assessed group (GA) with 6 subjects with different anthropometric characteristics. The GA had the skin markers placed by the 3 raters on the same day, with an interval between each assessment. A total of 4 images from each subject were taken for each rater’s assessment (GE), using a PENTAX – Optio 60 camera, on a tripod, adequately placed. Images were digitalized using a Fisio Office plus software generating 33 angular measures. The intra-class correlation coefficient (ICC) was used for the statistical analysis, associated to the standard error of measurement (SEM). Results: Twenty measurements were in agreement among the 3 raters. It was not possible to determine the influence of the anthropometric characteristics in placing the markers due to the limited sample size. Conclusion: The study has demonstrated agreement for 60% of the studied measurements indicating that skillful and well trained raters, who control the assessment conditions, do guarantee precision and accuracy in using photogrammetry to assess static posture. DESCRIPTORS Photogrammetry. Posture. Reproducibility of Results.