title: Test-retest reproducibility of elbow goniometric measurements in a rigid double-blinded protocol: intervals for distinguishing between measurement error and clinical change.
abstract: Increasingly, goniometry of elbow motion is used for qualification of research results. Expression of reliability is in parameters not suitable for comparison of results. We modified Bland and Altman's method, resulting in the smallest detectable differences (SDDs). Two raters measured elbow excursions in 42 individuals (144 ratings per test person) with an electronic digital inclinometer in a classical test-retest crossover study design. The SDDs were 0 +/- 4.2 degrees for active extension; 0 +/- 8.2 degrees for active flexion, both without upper arm fixation; 0 +/- 6.3 degrees for active extension; 0 +/- 5.7 degrees for active flexion; 0 +/- 7.4 degrees for passive flexion with upper arm fixation; 0 +/- 10.1 degrees for active flexion with upper arm retroflexion; and 0 +/- 8.5 degrees and 0 +/- 10.8 degrees for active and passive range of motion. Differences smaller than these SDDs found in clinical or research settings are attributable to measurement error and do not indicate improvement.
authors.affiliation: Department of Surgery, University Hospital Maastricht, Maastricht, The Netherlands. bcl@surgery.azm.nl
authors.forename: Berry
authors.initials: B
authors.lastname: Cleffken
authors.forename: Gerard
authors.initials: G
authors.lastname: van Breukelen
authors.forename: Henk
authors.initials: H
authors.lastname: van Mameren
authors.forename: Peter
authors.initials: P
authors.lastname: Brink
authors.forename: Steven
authors.initials: S
authors.lastname: Olde Damink
mesh_terms: D000328:Adult; D053587:Arthrometry, Articular / Q000295:instrumentation / Q000379:methods* / Q000592:standards; D018592:Cross-Over Studies; D004311:Double-Blind Method; D004551:Elbow Joint / Q000502:physiology* / Q000503:physiopathology / Q000601:surgery; D005260:Female; D006801:Humans; D008297:Male; D015588:Observer Variation; D019637:Orthopedic Procedures; D016059:Range of Motion, Articular; D012016:Reference Values; D015203:Reproducibility of Results; D016896:Treatment Outcome