Reliability of postural measures in elite badminton players using Posture Pro 8

The Posture Pro software is used for photogrammetry assessment of posture and has been commercially available for several years. Along with symmetry-related measures, a Posture Number® is calculated to reflect the sum of postural deviations. Our aim was to investigate the intra- and inter-rater reliability of measures extracted using the Posture Pro 8 software without using reference markers on subjects. Four raters assessed the standing posture of 40 badminton players (20 males, 20 females) from anterior, lateral, and posterior photographs. Thirty-three postural measures were extracted using visual landmarks as guide. Reliability was quantified using intra-class correlation coefficient (ICC) and typical error of measurement (TEM). Overall, the intra-rater reliability was considered good to excellent for nearly all measures. However, only two measures had excellent inter-rater reliability, with 13 and 18 measures exhibiting good and fair inter-rater reliability, respectively. Posture Pro specific measures (n = 9) exhibited good-to-excellent intra-rater and fair-to-excellent inter-rater reliability, with small-to-moderate and small-to-large TEM, respectively. Overall, the Posture Pro 8 software can be considered a reliable tool for assessing a range of posture-relevant measures from photographs, particularly when performed by the same examiner. The Posture Number® demonstrated generally acceptable intra- and inter-rater reliability. Nonetheless, investigations on the validity, sensitivity, and interpretation of this measure are essential to confirm its clinical relevance.