The responsiveness of the Shoulder Disability Questionnaire

• Published in: Annals of the rheumatic diseases Vol. 57; no. 2; pp. 82 - 87
• Main Authors: van der Windt, Daniëlle A W M, van der Heijden, Geert J M G, de Winter, Andrea F, Koes, Bart W, Devillé, Walter, Bouter, Lex M
• Format: Journal Article
• Language: English
• Published: London BMJ Publishing Group Ltd and European League Against Rheumatism 01.02.1998; BMJ; Elsevier Limited
• Subjects: Activities of Daily Living; Adolescent; Adult; Aged; Biological and medical sciences; Diseases of the osteoarticular system; Extended Reports; Family Practice; Female; Follow-Up Studies; functional disability; Humans; Male; Medical sciences; Middle Aged; Miscellaneous. Osteoarticular involvement in other diseases; Musculoskeletal Diseases - physiopathology; Musculoskeletal Diseases - therapy; Observational studies; outcome assessment; Pain; Pain - physiopathology; Pain Measurement; Patients; Physical therapy; Questionnaires; Ratios; responsiveness; ROC Curve; Sensitivity and Specificity; Severity of Illness Index; Shoulder; Surveys and Questionnaires; Treatment Outcome; Human; Evaluation; Prognosis; Questionnaire; Methodology; Treatment efficiency; Diseases of the osteoarticular system; Disability; Pain; Follow up study; Shoulder; Thoracic girdle; Upper limb
• ISSN: 0003-4967; 1468-2060
• DOI: 10.1136/ard.57.2.82

Objective—To evaluate the responsiveness of the Shoulder Disability Questionnaire (SDQ). Methods—The study was conducted within the framework of an observational study on shoulder disorders in primary care. After first presentation of their complaints to the general practitioner and after one and six months, participants completed the SDQ, a single question on functional status (FSQ), and an ordinal 11 point scale for the severity of pain (PSS). Responsiveness of the SDQ was evaluated compared with that of the FSQ and PSS, by calculating responsiveness ratios and by plotting receiver operating characteristic (ROC) curves. Recovery according to the patient was used as an external criterion for clinically relevant improvement (complete recovery or much improved on a six point Likert scale was denoted as clinically relevant improvement). Results—A total of 349 consecutive patients with shoulder disorders were enrolled in the observational study. Response rates ranged between 96% and 89%. Responsiveness ratios were slightly higher for the PSS compared with the SDQ (2.53 versus 2.22 at one month, 2.24 versus 1.89 at six months). The area under the ROC curve was 0.84 for both the SDQ and the PSS, and 0.72 for the FSQ. Conclusion—The results of this study confirm the responsiveness of the SDQ, making it a useful instrument to assess functional disability in longitudinal studies.