Inter-rater reliability of ultrasound measurements of acromion-greater tuberosity distance between experienced and novice raters in healthy people.

Abstract

Acromion-greater tuberosity (AGT) distance is used to assess shoulder pathologies including rotator cuff tears. The aim of this pilot study was, to provide short course of training and assess inter-rater reliability of ultrasonographic measurements of AGT distance between experienced and novice raters (physiotherapy students) in healthy individuals prior to testing on patient populations. Eleven healthy individuals with a mean age 54 years (SD 5) who gave informed written consent were recruited. Three final year physiotherapy students acted as novice raters and an experience rater (physiotherapist) recorded the ultrasound measurements of AGT distance on both shoulders using a standardised protocol. ICC values for inter-rater reliability between experienced rater and novice raters 1, 2 and 3 for the left shoulder were 0.83 (95% CI 0.63-0.94), 0.87 (95% CI 0.73-0.96) and 0.61 (95% CI 0.37-0.85) respectively. Corresponding values for the right shoulder were 0.85 (95% CI 0.70- 0.95), 0.75 (95% CI 0.55-0.91) and 0.62 (95% CI 0.38-0.85). The standard error of measurement (SEM) and minimum detectable change (MDC) were ≤0.2cm and ≤0.3 cm respectively for all the raters. Evidence from this study provides further support for the potential usefulness of ultrasound in both research and clinical practice for the management of shoulder pathologies.