Validation of a New Arabic Version of the Neuropathic Pain Diagnostic Questionnaire (DN4)

The "Douleur Neuropathique 4 (DN4) questionnaire" was developed for screening neuropathic pain. The purpose of this work was to validate the DN4 questionnaire in the standard Arabic language. First, the questionnaire was translated and semantically adapted to Arabic according to the international guidelines for cross-cultural adaptation. Second, a prospective observational study was performed to validate this questionnaire. A total of 195 patients with chronic pain (n = 99 with neuropathic pain and n = 96 without neuropathic pain) were enrolled in the study. The internal consistency Kuder-Richardson's Formula 20 for the whole DN4 questionnaire was 0.86 (P < 0.001) and the intraclass correlation coefficient 0.99 (95% CI: 0.99 to 1.00). The test-retest reliability kappa coefficient for each item ranged from 0.92 to 1.00. Using a receiver-operating characteristic (ROC) curve analysis, the areas under the curve were 0.94 and 0.97 for the 7-item DN4 and 10-item DN4, respectively. A cut-off score of 3 resulted in a sensitivity of 97.0% and a specificity of 82.3% for the 7-item DN4, while a cut-off score of 5 for the 10-item DN4 resulted in a sensitivity of 93.0% and a specificity of 95.8%. Tingling, numbness, and hypoesthesia to touch and to pricking were the most discriminating pain items. The sensitivity and specificity of the 7-item DN4 and 10-item DN4 were not influenced by either pain severity or educational level. In conclusion, this new Arabic version DN4 questionnaire is a simple, reliable, and valid tool for discriminating between neuropathic and non-neuropathic pain. It represents a useful tool in clinical setting and population-based studies.