Use of Numeric Rating Scale (NRS) as Visual Analogue Scale (VAS): Is this Clinically Significant?

Objective: To analyze statistically significant differences between the Numeric Rating Scale (NRS) and Visual Analogue Scale (VAS) in low back pain (LBP) patients. Study Design: Prospective longitudinal Study. Place and Duration of Study: Orthopaedic and Spine Department, Combined Military Hospital, Peshawar Pakistan, from Sep 2019 to May 2020. Methodology: The study included two hundred one patients with low back pain presented to the Orthopedic and Spine OPD.All patients were asked to record their pain with a Visual Analogue Scale (VAS) at the start of the visit and a Numerical Rating Scale (NRS) at the exit, at approximately 5-7 minute intervals in the Outpatient Department. Results: Two hundred one patients were included in the study. The mean age of the patients was 41.5 years (range 15-75). Thecomparison of pain measurements with the Numerical Rating Scale (NRS) showed a mean of 7.408(SD1.853), whereas with the Visual Analogue Scale (VAS), it was 6.864 (SD1.954). This showed higher readings with NRS compared to VAS, with a mean difference of 0.544 (p-value was