Intertester reliability of a classification system for shoulder pain

ObjectiveTo describe and determine the intertester reliability of a newly developed classification system of shoulder syndrome recognition.DesignIntertester reliability study.SettingFourteen primary care physiotherapy clinics.ParticipantsTwo hundred and fifty-five patients with shoulder pain. Inclusion criterion: presence of shoulder pain aring within the glenohumeral or associated joints and structures. Exclusion criteria: previous shoulder surgery, surgical candidates, recognised malignancy, systemic illness, or concurrent cervical pain and/or radiculopathy.InterventionExaminers were 55 physiotherapists who were arranged in pairs; each patient received two independent and blinded assessments, one by each of the paired physiotherapists. This shoulder classification approach contains three main clinical syndromes: Pattern 1 (impingement pain), Pattern 2 (acromioclavicular joint pain) and Pattern 3 (shoulder pain: frozen shoulder, glenohumeral arthritis, massive cuff tear, subscapularis tear, painful laxity, post-traumatic instability, internal derangement).Main outcome measuresPercentage agreement and Cohen's kappa coefficient.ResultsThe mean age of patients was 46.6 years (standard deviation 16.3, range 16 to 86), and 57% were male. Physiotherapists agreed on the pattern of shoulder pain for 205 of the 255 shoulders assessed (agreement rate 80%); the kappa coefficient was 0.664 (95% confidence interval 0.622 to 0.706; P < 0.001). Of the 205 agreements, Pattern 1 was the most common condition; physiotherapists agreed on this pattern for 139 patients (68%). Both physiotherapists diagnosed Pattern 2 for 20 patients and Pattern 3 for 46 patients.ConclusionThis clearly defined system uses key elements of the history and examination to classify patients with shoulder pain. The kappa coefficient denotes good reproducibility.