Cut-Off Points for Mild, Moderate, and Severe Pain on the Numeric Rating Scale for Pain in Patients with Chronic Musculoskeletal Pain: Variability and Influence of Sex and Catastrophizing

Abstract

Objectives: The 0–10 Numeric Rating Scale (NRS) is often used in pain management. The aims of our study were to determine the cut-off points for mild, moderate, and severe pain in terms of pain-related interference with functioning in patients with chronic musculoskeletal pain, to measure the variability of the optimal cut-off points, and to determine the influence of patients’ catastrophizing and their sex on these cut-off points.Methods: 2854 patients were included. Pain was assessed by the NRS, functioning by the Pain Disability Index (PDI) and catastrophizing by the Pain Catastrophizing Scale (PCS). Cut-off point schemes were tested using ANOVAs with and without using the PSC scores or sex as co-variates and with the interaction between CP scheme and PCS score and sex, respectively. The variability of the optimal cut-off point schemes was quantified using bootstrapping procedure.Results and conclusion: The study showed that NRS scores ≤ 5 correspond to mild, scores of 6–7 to moderate and scores ≥8 to severe pain in terms of pain-related interference with functioning. Bootstrapping analysis identified this optimal NRS cut-off point scheme in 90% of the bootstrapping samples. The interpretation of the NRS is independent of sex, but seems to depend on catastrophizing. In patients with high catastrophizing tendency, the optimal cut-off point scheme equals that for the total study sample, but in patients with a low catastrophizing tendency, NRS scores ≤ 3 correspond to mild, scores of 4–6 to moderate and scores ≥7 to severe pain in terms of interference with functioning. In these optimal cut-off schemes, NRS scores of 4 and 5 correspond to moderate interference with functioning for patients with low catastrophizing tendency and to mild interference for patients with high catastrophizing tendency. Theoretically one would therefore expect that among the patients with NRS scores 4 and 5 there would be a higher average PDI score for those with low catastrophizing than for those with high catastrophizing. However, we found the opposite. The fact that we did not find the same optimal CP scheme in the subgroups with lower and higher catastrophizing tendency may be due to chance variability.

Validity, cut-points, and minimally important differences for two hot flash-related daily interference scales

“…Data-driven approaches to establishing severity and interference cutpoints have resulted in equivocal findings across samples and across symptoms. 34–37 Using common cutpoints ensures easier translation into practice.…”

Impact of frailty on chronic pain, activities of daily living and physical activity in community‐dwelling older adults: A cross‐sectional study

“…Participants were asked to identify pain sites and intensity on the chart using the NRS. Pain intensity at the site of maximum pain was categorized as mild (NRS score ≤3), moderate (NRS score of 4–6) or severe (NRS score ≥7) . We also assessed the presence of chronic pain, which was defined as related symptoms within the past month that had continued for at least 6 months and corresponded to an NRS score of ≥5 at the site of maximum pain .…”

Prevalence of symptoms at the end of life in an acute care hospital: a retrospective cohort study

“…We used this threshold to capture pain that was likely causing distress and not simply a nuisance. [21][22][23] During the study period, our hospital had an hourly rounding policy that required nurses to assess each patient every hour. There was, however, no standardized treatment pathway to deal with symptoms.…”