Part I: Validity and reliability of a photographic method for postural assessement (PMPA).

Abstract

Introduction: Good postural alignment is positively associated with safe, mechanically effective and meaningful engagement in occupations. Health care professionals assess posture in clinical settings by using a variety of methods ranging from simple visual observation, to more complex quantitative assessments of postural alignment, which are costly and mostly done in laboratory environments. The need exists for a cost effective and user-friendly method for the assessment of posture in clinical settings and research studies.

Objectives: The aim of this study was to develop a Photographic Method of Postural Assessment (P-MPA) that quantitatively measures postural alignment, and to determine the validity and reliability of the P-MPA.

Methods: A graph, representing graphic postural alignment, was used consisting of a vertical line that represents the five levels of anatomical landmarks, with a horizontal line crossing the vertical line at each of the five levels. A total of 20 points were randomly plotted on the five horizontal lines.  The graph was photographed using a smartphone, and A4 sized photographs were printed.  Fifty participants measured and noted the distance deviations between the points on the horizontal lines and the vertical line. The actual deviation from the vertical line was calculated using a ratio of measured to real distance. 

Results: The distance deviation between measured and actual distances was statistically significant for certain anatomical landmarks as indicated by 95% Confidence Intervals and Limits of Agreement. With respect to the anatomical landmarks and respective points, no clinically significant differences were observed, as a difference of less than 10mm was found. 

Recommendations: It is recommended that the P-MPA be used, as a user-friendly and cost-effective method, for measuring postural alignment in clinical settings, and, that it be further developed and investigated as measurement tool for both single and multiple-joint research studies during activity performance.

Keywords:  Posture assessment, validity, reliability