Reliability intra-and inter-examiner of the head postural assessment by computerized photogrammetry

Abstract

Scientific articles about reliability of photogrammetry for cervical spine posture evaluation are infrequent. The aim of the present investigation is to verify intra-and inter-examiner reliability of the computerized photogrammetry method for head postural evaluation in lateral view. Twenty-five young women, between 20 and 30 years old, were positioned seated in an upright position and photographed in lateral view. The photographs were imported to Corel Draw X13 program for postural evaluation by computerized photogrammetry. Analyses of intra-and inter-examiner reliability were performed for the angles: condyle-acromion (ACA), menton-sternum (AME) and Frankfurt (AF). The photogrammetry was performed by two examiners: EA and EB. For intra-examiner analyses, EA assessed the pictures twice (A1 and A2) for the same angles within 3 months. For the inter-examiner analyses, EB performed the photogrammetry for the same angles (B1) in order to compare with the data from EA. Using the interclass correlation coefficient (ICC) we observed an excellent correlation in the intra-examiner analysis (A1 and A2) for the angles: ACA and AME (both with ICC=1.0); and AF (ICC=0.78). For the inter-examiner analyses between A1 and B1, it was observed: ACA (ICC=0.24), AME (ICC=0.26) and AF (ICC=0.00). For the comparison between A2 and B1, the ICC values were: 0.23; 0.27 and 0.00, respectively for ACA, AME and AF, classified as weak correlations. In conclusion, the photogrammetry is reliable when performed by the same examiner. The inter-examiner assess showed low reliability, what could have been compromised by the reduced experience of the EB in applying the method.