Abstract
Background
Routine assessments of pain using an intensity numeric rating scale (NRS) have improved documentation, but have not improved clinical outcomes. This may be, in part, due to the failure of the NRS to adequately predict patients’ preferences for additional treatment.
Objective
To examine whether patients’ illness perceptions have a stronger association with patient treatment preferences than the pain intensity NRS.
Design
Single face-to-face interview.
Participants
Outpatients with chronic, noncancer, musculoskeletal pain.
Main Measures
Experience of pain was measured using 18 illness perception items. Factor analysis of these items found that five factors accounted for 67.1% of the variance; 38% of the variance was accounted for by a single factor labeled “pain impact.” Generalized linear models were used to examine how NRS scores and physical function compare with pain impact in predicting preferences for highly effective/high-risk treatment.
Key Results
Two hundred forty-nine subjects agreed to participate. Neither NRS nor functioning predicted patient preference (NRS: χ2 = 1.92, df = 1, p = 0.16, physical functioning: χ2 = 2.48, df = 1, p = 0.11). In contrast, pain impact was significantly associated with the preference for a riskier/more effective treatment after adjusting for age, comorbidity, efficacy of current medications and numeracy (χ2 = 4.40, df = 1, p = 0.04).
Conclusions
Tools that measure the impact of pain may be a more valuable screening instrument than the NRS. Further research is now needed to determine if measuring the impact of pain in clinical practice is more effective at triggering appropriate management than more restricted measures of pain such as the NRS.
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Acknowledgement
We would like to thank Marion Michalski for her dedication to the subjects of this study. To the best of our knowledge, no conflict of interest, financial or other, exists. This work was supported by VA Health Services and Research Department grant no. IIR 07-090-3.
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This grant was supported by VA Health Services and Research Department grant no. IIR07-090-3.
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Fraenkel, L., Falzer, P., Fried, T. et al. Measuring Pain Impact Versus Pain Severity Using a Numeric Rating Scale. J GEN INTERN MED 27, 555–560 (2012). https://doi.org/10.1007/s11606-011-1926-z
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DOI: https://doi.org/10.1007/s11606-011-1926-z