Pelvic tilt in sitting: Do you see what I see? (Maybe not)

Examination of pelvic tilt movements are utilised across many fields of physiotherapy. It is important for physiotherapists to establish a clinically helpful, time-efficient test assessing pelvic tilt, reliable within and across multiple assessors. Elgueta-Cancino et al. (2014) described such a test; however, their methodology reduced clinical applicability and revealed limitations regarding examination of test reliability. This study aimed to independently evaluate the reliability of a clinical test of pelvic tilt. Twenty-three participants with chronic low back pain completed the test following standardised instructions and demonstration by one assessor. Participants tilted the pelvis forwards and backwards 10 times in sitting. The test was simultaneously scored on the scale originally described by three blinded assessors. Participants repeated the test one-week later. Inter-assessor reliability was determined using an intraclass correlation coefficient (ICC 2,1), with a resulting value of 0.52, 95% confidence interval [0.35-0.68]; and a standard error of measurement SEM (with a resulting value of 1.28). The following SEM values were found for intra-assessor agreement: Assessor 1 =1.52, assessor 2 =1.47, and assessor 3 = 1.19. These findings suggest the inter- and intra-assessor reliability of a clinical test of pelvic tilting has insufficient reliability to distinguish between participants across multiple assessors. An observed change of at least 1.5 points may be necessary to be confident true change in test performance has occurred. Key Words: Low Back Pain, Movement Control, Reliability