Pain Scales: What Are They and What Do They Mean.

PURPOSE OF REVIEW: It is essential to have validated and reliable pain measurement tools that cover a wide range of areas and are tailored to individual patients to ensure effective pain management. The main objective of this review is to provide comprehensive information on commonly used pain scales and questionnaires, including their usefulness, intended purpose, applicability to different patient populations, and associated advantages and disadvantages. RECENT FINDINGS: Acute pain questionnaires typically focus on measuring the severity of pain and the extent of relief achieved through interventions. Chronic pain questionnaires evaluate additional aspects such as pain-related functional limitations, psychological distress, and psychological well-being. The selection of an appropriate pain scale depends on the specific assessment objectives. Additionally, each pain scale has its strengths and limitations. Understanding the differences among these pain scales is essential for selecting the most appropriate tool tailored to individual patient needs in different settings. CONCLUSION: Medical professionals encounter challenges in accurately assessing pain. Physicians must be familiar with the different pain scales and their applicability to specific patient population.

Comparing pain intensity rating scales in acute postoperative pain: boundary values and category disagreements.

Pain intensity assessment scales are important in evaluating postoperative pain and guiding management. Different scales can be used for patients to self-report their pain, but research determining cut points between mild, moderate and severe pain has been limited to studies with < 1500 patients. We examined 13,017 simultaneous acute postoperative pain ratings from 913 patients taken at rest and on activity, between 4 h and 48 h following surgery using both a verbal rating scale (no, mild, moderate or severe pain) and 0-100 mm visual analogue scale. We determined the best cut points on the visual analogue scale between mild and moderate pain as 35 mm, and moderate and severe pain as 80 mm. These remained consistent for pain at rest and on activity, and over time. We also explored the presence of category disagreements, defined as patients verbally describing no or mild pain scored above the mild/moderate cut point on the visual analogue scale, and patients verbally describing moderate or severe pain scored below the mild/moderate cut point on the visual analogue scale. Using 30 and 60 mm cut points, 1533 observations (12%) showed a category disagreement and using 35 and 80 mm cut points, 1632 (13%) showed a category disagreement. Around 1 in 8 simultaneous pain scores implausibly disagreed, possibly resulting in incorrect pain reporting. The reasons are not known but low rates of literacy and numeracy may be contributing factors. Understanding these disagreements between pain scales is important for pain research and medical practice.

Ability of pain scoring scales to differentiate between patients desiring analgesia and those who do not in the emergency department.

BACKGROUND AND IMPORTANCE: Pain is one of the most reasons for a visit to an emergency department (ED). Pain scores as the verbal rating scale (VRS) or numerical rating scale (NRS) are used to determine pain management. While it is crucial to measure pain levels, it is equally important to identify patients who desire pain medication, so that adequate provision of analgesia can occur. OBJECTIVE: To establish the association between pain scores on the NRS and VRS, and the desire for, and provision of, pain medication. DESIGN, SETTINGS AND PARTICIPANTS: Retrospective monocentric observational cohort study of ED patients presenting with painful conditions. OUTCOMES MEASURE AND ANALYSIS: The primary outcome was to establish for each pain score (NRS and/or VRS), those patients who desired, and were ultimately provided with, pain medication, and those who did not. Secondary outcomes included establishing the prediction of pain scores to determine desire of pain medication, and the correlation between NRS and VRS when both were reported. MAIN RESULTS: 130,279 patients were included for analysis. For each patient who desired pain medication, pain medication was provided. Proportion of patients desiring pain medication were 4.1-17.8% in the pain score range 0.5-3.5, 31.9-63.4% in the range 4-6.5, and 65-84.6% in the range 7-10. The prediction probability of pain scores to determine desire for pain medication was represented with an AUROC of 0.829 (95% CI 0.826-0.831). The optimal threshold predicting the desire for pain medication would be a pain score of 4.25, with sensitivity 0.86, and specificity 0.68. For the 7835 patients with both NRS and VRS scores available, the Spearman-Rho coefficient assessing correlation was 0.946 (p < 0.001). CONCLUSIONS: Despite guidelines currently recommending pain medication in patients with a NRS score > 4, we found a discrepancy between pain scores and desire for pain medication. Results of this large retrospective cohort support that the desire for pain medication in the ED might not be derived from a pain score alone.

Comparing the measurement properties of visual analogue and verbal rating scales.

PURPOSE: Utilising Rasch analysis on the Keratoconus Outcome Research Questionnaire (KORQ) data, we explored the hypothesis that the KORQ with discrete verbal rating scale (VRS) would demonstrate better psychometric properties and provide less noise in measurement than with a visual analogue scale (VAS). METHODS: The KORQ is a keratoconus-specific patient-reported outcome measure; it has activity limitation and symptoms scales. The KORQ scales with two different rating scales (VAS and a discrete 4-response VRS) were completed by self-administration by people with keratoconus. For each KORQ scale, Rasch analysis-based psychometric properties were compared between the two versions. Rasch analysis was also used to optimise rating scale functioning when disordered thresholds were observed. RESULTS: 118 (mean age ± SD, 46.4 ± 0.4 years) and 169 (45.4 ± 14.7 years) people completed the KORQ with VAS and VRS, respectively. Both scales demonstrated high measurement precision. However, the VAS rating scale was disordered (6 out of 11 categories dysfunctional) and had two misfitting items. Conversely, the VRS had ordered categories and no misfitting items. For the disordered VAS, ordering was achieved only after collapsing 11 categories into four categories. In comparison to the KORQ with VRS, the repaired VAS had lower measurement precision, test information, variance explained by the measure, poor targeting, and reduced measurement range. CONCLUSIONS: The KORQ demonstrated superior psychometric properties when measured using a VRS than with a VAS. This illustrates the advantages of verbal rating scales for a patient-reported outcome measurement over a visual analogue scale.

Interpretation of verbal descriptors for response options commonly used in verbal rating scales in patient-reported outcome instruments.

PURPOSE: To assess the variation in the interpretation of common verbal descriptors (VDs) used in response scales and examine factors associated with those interpretations. METHODS: Subjects were recruited through MediGuard and they assigned interpretation scores (11-point scale; 0 = lowest possible, 10 = highest possible) to five common sets of VDs: set one (none, mild, moderate, severe, very severe); set two (never, rarely, sometimes, often, always); set three (poor, fair, good, very good, excellent); set four (not at all, a little bit, moderately, quite a bit, extremely); and set five (not at all, a little bit, somewhat, quite a bit, very much). One-sample test for proportions and T-tests examined equality of proportions (anchors) and means scores (non-anchors) with the fixed intervals (0.0, 2.5, 5.0, 7.5, and 10.0). Ordinal regression examined adjusted associations between demographic/clinical factors and VD scores. RESULTS: Of the 350 subjects, 68 % were females and mean (SD) age was 56.9 (12.1). Two sets had two VDs with mean (95 % CI) scores not different than the fixed intervals. Set one had mild = 2.50 (2.33; 2.66) and moderate = 5.01 (4.89; 5.13) with 98.8 % (97.3 %; 100 %) assigning none = 0. Set five had a little bit = 2.35 (2.17; 2.53) and quite a bit = 7.65 (7.43; 7.87) with 95.0 % (95 % CI 91.7; 98.2) assigning not at all = 0. Significant associations (p ≤ 0.05) included age and education with somewhat and income and comorbidities with very severe. Age, sex, and education showed associations with other VDs albeit in nonsignificant models. CONCLUSIONS: Sets one and five yielded data closest to the fixed intervals. Demographic and clinical factors are associated with the interpretation of some VDs and should be adjusted for in analyses of non-randomized data.

Measuring the Intensity of Chronic Pain: Are the Visual Analogue Scale and the Verbal Rating Scale Interchangeable?

OBJECTIVES: The 0 to 100 mm visual analogue scale (VAS) and the five-category verbal rating scale (VRS) are commonly used for measuring pain intensity. An open question remains as to whether these scales can be used interchangeably to allow comparisons between intensities of pain in the clinical setting or increased statistical power in pain research. METHODS: Seven hundred and ninety-six patients were requested to rate the present intensity of their chronic pain on the two scales. Spearman's rank correlation coefficients between VAS and VRS were calculated. For testing interchangeability, VAS was transformed into a discrete ordinal scale by dividing the entire VAS into five categories, either equidistantly (biased) or using frequency distributions of VAS (unbiased). We used Goodman-Kruskal's gamma and Wilson's e measures of ordinal association quantified the relationships between the transformed VAS and VRS scores and Svensson method to evaluate agreement between biased and unbiased discrete VAS and VRS scales. RESULTS: Average VAS and VRS scores were 76 ± 18 mm and "severe," respectively. Spearman's rank correlation coefficient values between continuous VAS and VRS were 0.77 to 0.85. Goodman-Kruskal's gamma ordinal associations between discrete VAS and VRS were 0.82 to 0.92 and 0.90 to 0.98 for the biased and unbiased VAS, respectively. Wilson's e measures were 0.51 to 0.61 and 0.54 to 0.65, accordingly. Svensson analysis showed low probability of agreement between both biased (0.66 to 0.76) and unbiased (0.75 to 0.82) VAS and VRS. DISCUSSION: Regardless of the relatively high Spearman correlations between original VAS and VRS, the low ordinal association and low probability of agreement between discrete VAS and VRS suggest that they are not interchangeable. Therefore, VAS and VRS should not be used interchangeably in the clinical setting or for increased statistical power in pain research.

Therapeutic efficacy of Lofnac Gel via phonophoresis in the management of chronic nonspecific low back pain: A randomised controlled trial.

BACKGROUND: The prevalence of nonspecific low back pain is very high among Nigerians and in Africa. Lofnac Gel is a nonsteroidal anti-inflammatory gel that has been used to treat musculoskeletal pain, but its efficacy on nonspecific low back pain is inconclusive. OBJECTIVE: The objective of this study was to examine the therapeutic efficacy of Lofnac Gel in the management of nonspecific low back pain. METHODS: Seventy patients diagnosed with mechanical low back pain of 3 months' duration were divided into two groups: experimental group (n = 35) and control group (n = 35). Participants in both groups were placed on supervised strengthening exercises for multifidus muscles of the low back. The experimental group was placed on ultrasound phonophoresis therapy with Lofnac Gel (with diclofenac and methyl salicylate as active ingredients), whereas the control group was placed on ultrasound with water as coupling medium. The treatment was applied twice per week for 6 weeks. Present pain intensity and disability were measured before treatment, and in the 3rd week and 6th week of treatment. Data were analysed using descriptive and inferential statistics, and post hoc analysis was carried out when necessary. RESULTS: There was a significant difference between the pre- and posttreatment pain intensity and disability index for both the experimental (F = 17.947, p < 0.001; F = 20.712, p < 0.001) and control (F = 14.791, p < 0.001; F = 10.418, p < 0.001) groups. There was also a significant difference between the experimental and control group data in terms of pain intensity (F = 28.76, p < 0.001) and disability index (F = 39.817, p < 0.001) in the 6th week. CONCLUSION: Exercise combined with Lofnac phonophoresis was more effective in the management of patients with chronic low back pain than exercise and ultrasound alone.

Comparing the Effects of Intramuscular Injections of Dexamethasone and Ketorolac Tromethamine on Post-treatment Endodontic Pain: An In Vivo Study.

BACKGROUND AND OBJECTIVES: Pain is the primary reason dental patients seek endodontic therapy. Post-treatment endodontic discomfort is a sequelae of periapical inflammation and anti-inflammatory drugs such as corticosteroids and non-steroidal anti-inflammatory drugs (NSAIDs) would be reasonable therapy options. The purpose of this study was to compare and assess the efficacy of intramuscular injections of dexamethasone and ketorolac tromethamine versus placebo in reducing post-treatment endodontic pain in individuals undergoing root canal treatment. METHODOLOGY: Patients diagnosed with symptomatic irreversible pulpitis were selected. Nonsurgical endodontic therapy was carried out in a single visit. After completion of the root canal therapy, the patients were randomly assigned to one of the three groups for intramuscular drug administration. In group 1, 2 ml of sterile saline was administered, in group 2, 1 ml of 4 mg dexamethasone was administered; and in group 3, 1 ml of 30 mg ketorolac tromethamine was administered. Preoperative and postoperative pain intensity was measured by a verbal rating scale. Postoperatively, the incidence and severity of pain were recorded after four, 24, and 48 hours. RESULTS: All three groups showed a highly statistically significant reduction in pain scores when compared to preoperative levels. At the end of four hours, dexamethasone and ketorolac tromethamine showed highly significant results. Dexamethasone significantly reduced pain after 24 hours when compared to ketorolac and placebo groups. At the conclusion of 48 hours, all three groups experienced a gradual decrease in pain levels. CONCLUSION: Effective and complete debridement of infected root canal system provides predictable gradual reduction of post-endodontic pain.

What is the analgesic range of acupuncture stimulus for treating acute pain?

Introduction: Since the analgesic effect of acupuncture stimulation is derived from different mechanisms depending on the type of pain, it is important to know which acupuncture points to stimulate. In this study, to confirm the effect of acupuncture stimulation on acute pain from a neurological point of view, somatosensory evoked potential and sensory threshold changes were evaluated to identify the nerve range that is affected by acupuncture stimulation on LI4 (Hapgok acupuncture point, of the radial nerve) during acute pain. Methods: The subjects were 40 healthy men and women aged 19-35 years. The study was designed as a randomly controlled, crossover trial with acupuncture stimulation at LI4 as the intervention. The washout period for acupuncture stimulation was 2 weeks, and the subjects were divided into two groups, i.e., an acupuncture stimulation group and a nonstimulation group, with 10 men and 10 women in each group. Somatosensory evoked potential measurement was carried out for 5 min by alternately applying 2 HZ-pulse electrical stimulation to the thumb and the little finger of the hand acupunctured with a 64-channel electroencephalogram. The verbal rating scale was used before and after each acupuncture stimulation session. Result and discussion: The results of the study confirmed that the somatosensory evoked potential amplitude value of the thumb was significantly decreased and that the intensity of sensory stimulation corresponding to a verbal rating scale score of 6 was significantly increased only in the thumb after acupuncture stimulation. Therefore, the results show that acupuncture treatment for acute pain is more effective when direct acupuncture stimulation is applied to the painful area.