Could numeric rating scale take the place of neck disability index, as a self-reported instrument of the neck/arm pain-related daily living disability, in patients with cervical radiculopathy?

Background: Quantification of neck and upper extremity pain-related disability is crucial for treatment selection and, finally, for assessing clinical outcomes of the selected treatment in patients with cervical radiculopathy. The objective of this study was to investigate the correlation between the Neck Disability Index (NDI) and the properly adapted Numeric Rating Scale (NRS) in the context of a neck/arm pain-related daily living disability self-report instrument in patients with cervical radiculopathy. Methods: Data from 75 patients with neck/arm pain due to radiculopathy were collected. NRS was used to obtain the self-reported neck/arm pain severity. NDI and a proper adaptation of the NRS were used to obtain the self-reported daily living disability due to neck/arm pain. Results: There was “mild”, statistically significant, positive correlation between NRS for neck/arm pain severity and NDI (r = 0.351, P = 0.001) as well as “mild”, statistically significant, positive correlation between NRS for pain influence on daily living activities and NDI (r = 0.417, P = 0.000). Additionally, the NDI value could be predicted in a low percentage of 16% based on preoperative NRS for pain influence on daily living activities.