Objective: To develop a standardized protocol for measurement of shoulder movements using a gravity inclinometer designed for use in clinical trials, and to assess its intra- and interrater reliability in a group of manipulative physiotherapists.
Methods: After instruction, 6 manipulative physiotherapists independently assessed 8 movements of the shoulder, including total and glenohumeral flexion (TF, GHF), total and glenohumeral abduction (TA, GHA), external rotation in neutral (ERN) and abduction (ERA), internal rotation in abduction (IRA), and hand behind back (HBB), in random order in 6 patients with shoulder pain and stiffness according to a 6 x 6 Latin square design using the standardized protocol. The assessments were then repeated. Analysis of variance was used to partition total variability into components of variance in order to calculate intraclass correlation coefficients (ICCs).
Results: The intra- and interrater reliability of the different movements varied widely. Reliability was higher for TF and TA than for the corresponding glenohumeral movements (e.g., intrarater ICCs: TF = 0.80, GHF = 0.65, TA = 0.75, GHA = 0.62). Interrater reliability was higher in the second round suggesting a practice effect (e.g., round 1, 2 interrater ICCs TF = 0.62, 0.82; TA = 0.62, 0.88; ERN = 0.85, 0.95).
Conclusion: The measurement of the active range of TF, TA, ERN, and HBB, measured by manipulative physiotherapists following the standardized protocol, has intra- and interrater reliability acceptable for use as an outcome measure in clinical trials assessing interventions for shoulder pain.