Relatively short term test re-test reliability of Neck Disability Index by long term test re-retest reliability method of Oswestry Disability Index in healthy office workers.

Abstract

Assessment of local condition specific outcome measures in combination to obtain an idea about the disability status of the whole spine is a conventional method. Oswestry Disability Index (ODI) and Neck Disability Index (NDI) are two outcome measures used together. Test re-test reliability of ODI in healthy subjects has clinical importance and the test re-test reliability of NDI may have clinical significance. The purpose of this study is to investigate the test re-test reliability of the NDI by using long-term test re-test reliability method of ODI on healthy office workers. Participants who have no chronic neck pain history were included in the study. Subjects were assessed by the Turkish-NDI (e-forms) on 1st, 2nd, 4th, 8th, 15th, 30th days. 49 (20 female, 29 male) of 106 participants (57 female, 49 male) completed the study. Kolmogorov-Smirnov and Friedman tests were used. The difference between median score of each day (χ= 9.275, p > 0.05) was neither statistically nor clinically significant. NDI has test re-test reliability in healthy subjects over a 1-month time interval and the test re-test reliability is also valid in cases where both questionnaires are used in combination in this time interval.