Psychometric and accuracy comparison of three commonly used questionnaires for the diagnosis of neuropathic pain.

Abstract

Objectives:Diagnosis of neuropathic pain is challenging. Recently, scientists developed multiple questionnaires to expedite this diagnosis including the Self-completed Leeds Assessment of Neuropathic Symptoms and Signs (S-LANSS), Douleur Neuropathique 4 questionnaire (DN4), and Neuropathic Pain Questionnaire–Short Form (NPQ-SF).Materials and Methods:We conducted a prospective cohort study to compare the psychometric characteristics and accuracy of the three questionnaires. We assessed reliability with the Cronbach's α reliability coefficient and inter-item correlations, and validity with receiver operating characteristic (ROC) and correlation analyses. We assessed agreement between the diagnosis of the questionnaires and the reference clinical diagnosis using Cohen's kappa coefficient.Results:188 patients were analyzed: 141 (75%) had “definite neuropathic” and 47 (25%) had “nonneuropathic” pain. The NPQ-SF and S-LANSS questionnaires demonstrated acceptable reliability with Cronbach's α coefficient values of 0.54 (95% CI: 0.41–0.64) and 0.65, (95%CI: 0.57–0.72), respectively. The DN4 questionnaire demonstrated high reliability with Cronbach's α coefficient of 0.74 (95%CI: 0.68–0.79). The NPQ-SF, DN4, and S-LANSS questionnaires demonstrated “excellent” diagnostic ability with an area under the ROC curve of 0.82 (95% CI: 0.75–0.89), 0.89 (95% CI: 0.83–0.95), and 0.83 (95% CI: 0.75–0.90), respectively. Based on their optimal cutoff values, the DN4 had the highest sensitivity and lowest specificity in discriminating between neuropathic and nonneuropathic patients, while the S-LANSS had the lowest sensitivity and highest specificity.Conclusion:Both NPQ-SF and S-LANSS demonstrated acceptable reliability, while DN4 demonstrated high reliability. All three demonstrated excellent diagnostic validities; however, it is important to consider the sensitivity and specificity of each.