Test Retest Reliability and Validity of Hindi Version of Neck Disability Index in Patients with Neck Pain

Non-Experimental Methodological design.

To translate and culturally adapt the Hindi version of Neck Disability Index and check its test retest reliability and validity in patients with neck pain.

The NDI is one of the most widely used reliable and valid instrument for assessing functional disabilities in NP patients. However, no reliable and valid tool is available in Hindi language.

The study was carried out in three phases: the first was translation into Hindi and cultural adaptation of the questionnaire, the second was a pilot study to assess the comprehensibility of the pre final version; third was the reliability and validity study of the final version of the questionnaire. The Hindi version was tested on 150 patients with neck pain. Test retest reliability and internal consistency were investigated.

Test retest reliability was assessed with 150 patients with a time interval of 48 hours. The intra class correlation coefficient of test retest reliability was 0.98 with all items having individual ICC scores ranging from 0.868 to 0. 986. Reliability estimated by the internal consistency reached a Cronbach's alpha of 0.995. The NDI subscales showed excellent test retest reliability with Cronbach's alpha ranging from 0.929 to 0.993. The Wilcoxon non parametric test was done for chance error which was negligible for almost all items.

The results of this study indicate that the Hindi version of the NDI is a reliable and valid tool for measuring disability caused due to neck pain in Hindi speaking Indian population. The authors recommend this Hindi version of the NDI for use in further future clinical studies in India.