Investigation of the validity of postural evaluation skills in assessing lumbar lordosis using photographs of clothed subjects.

Data for this study was collected at the 1988 Texas Physical Therapy Association Annual Conference with approval through the state Research Committee. The opinions or assertions contained herein are the private views of the authors and are not to be construed as official or reflecting the views of the Army, the Department of Defense, or the US. Government. The purpose of this study was to evaluate the validity of physical therapists' visual postural evaluation skills in assessing lumbar lordosis using photographs of clothed subjects compared to actual radiographic measurements. The study also addressed the efficacy of the use of a plumb line in postural assessment. Forty-eight physical therapists (raters) participated. After completing a demographic questionnaire, raters were given a set of pictures showing sagittal views of three subjects and asked to rank order the subjects from most to least amount of lumbar lordosis. Raters were then given a second set of pictures with different subjects to evaluate. During this second trial, raters were given a plastic overlay with a hairline to use as a plumb line. Each rater evaluated one set of subjects with 7-8 degrees of difference in lordosis and one set with 13- 14 degrees of difference as measured radiographically. The raters' rank order of the pictures was interpreted as either correct or incorrect. For 96 trials, 9 responses were correct for an accuracy rate of 9.3%. The use of the hairline as a plumb line did not improve the raters' accuracy. A chi-square test showed no relationship between ratings except under circumstances related to the gluteal prominence body contour. The strongest trend in interrater reliability identified was that the raters' perception of increased lordosis may have been influenced by gluteal prominence. The results indicate low validity in assessing relative amounts of lumbar lordosis using photographs of clothed subjects. This preliminary study indicates the need for more research in this area using both pictures and live subjects. J Orthop Sports Phys Ther 1990;12(1):24-29.