Comparing Pain Intensity Using the Numeric Rating Scale and Defense and Veterans Pain Rating Scale in Patients Revisiting the Emergency Department

Abstract

Objective  To determine the relationship between Numeric Rating Scale (NRS) and Defense and Veterans Pain Rating Scale (DVPRS) as pain intensity measures, we compared pain scores to sociodemographic and treatment data in patients revisiting the emergency department (ED). Methods  After Institutional Review Board approval, 389 adults presenting within 30 days of an index visit were enrolled. Pain scores were classified as follows: 0-3 (mild), 4-7 (moderate), and 8-10 (high). Data were analyzed using descriptive analysis. Wilcoxon rank-sum test measured the association of pain score with gender. Pain scales were correlated using Spearman correlation coefficient. Pain scale association with opioid treatment was tested via ordinal logistic regression controlling for gender, home opioid use, and if ED revisit was for pain. Results  Average patient age was 49. Most patients were African American (68.4%), male (51.2%), and returned for pain (67.0%). As continuous measures, both scales were positively correlated with each other (p<0.0001). Pain score severity categories were distributed differently between the two scales (p=0.0085), decreasing by 8% in patients reporting high pain severity when using DVPRS. For both scales, the proportion of patients (1) administered opioids (p=0.0009 and p≤0.0001, respectively) and (2) discharged with opioids (p=0.0103 and p=0.0417, respectively) increased with pain severity. Discharge NRS (p=0.0001) (OR=3.2, 1.780-5.988) and DVPRS pain score categories (p<0.0001) (OR=2.7, 95% CI=1.63-4.473) were associated with revisits for pain.  Conclusions Our findings demonstrate a link between NRS and administration of opioid medications and suggest that DVPRS may better differentiate between moderate and high levels of pain in the ED setting.