Standard scales for measurement of functional outcome for cervical pain or dysfunction - A systematic review

Study Design. A systematic review was conducted. Objective. To identify, evaluate, and compare standard scales for assessing neck pain or dysfunction. Summary of Background Data. The degree of a patients neck pain or dysfunction can be evaluated using standardized scales at the time of a clinical encounter or during the performance of clinical research protocols. The choice of a scale with the most appropriate characteristics, however, is always a challenge to clinicians and researchers. Methods. Articles concerning scales for functional evaluation of neck pain or dysfunction were identified by computer searching of MEDLINE (January 1966 to June 1999) and CINAHL (1985 to 2000), citation tracking using the Citation Index, hand searching of relevant journals, and correspondence with experts. Results. Five standard scales were found. Three scales were remarkably similar in terms of structure and psychometric properties: the Neck Disability Index, the Copenhagen Neck Functional Disability Scale, and the Northwick Park Scale. However, only the first instrument has been revalidated in different study populations. The Neck Pain and Disability Scale provides a visual template for collection of information, but its usefulness is limited if the questionnaire must be read to the patient. The Patient-Specific Functional Scale is very sensitive to functional changes in individual patients, but comparisons between patients are virtually impossible. Conclusions. The five scales identified in this study have similar characteristics. The Neck Disability Index, however, has been revalidated more times for evaluation of patient groups. For individual patient follow-up evaluation, the Patient-Specific Functional Scale has high sensitivity to change, and thus represents a good choice for clinical use. The final choice should be tailored according to the target population and the purpose of the evaluation.