Objectives: To develop screening tools for neuropathic pain caused by spinal disorders, the Spine painDETECT questionnaire (SPDQ) and its short-form version (SF-SPDQ), by modifying the Japanese version of the painDETECT questionnaire (PDQ-J), and to validate these tools.
Methods: Using data from patients with neuropathic pain caused by spinal disorders (NeP-SD) and patients with nociceptive pain caused by joint disorders (NocP) as controls, we devised a scoring system for the SPDQ by calculating weighting coefficients for nine PDQ-J items. Simultaneously, we selected some items for the SF-SPDQ. Next, we conducted the validation study primarily using patients with a confirmed diagnosis (a multicenter study) and general patients (a web-based survey). Sensitivity, specificity, and the area under the receiver-operating characteristic curve (AUC), along with additional positive/negative predictive values and positive/negative likelihood ratios, were calculated to assess the diagnostic utility of these tools in each population.
Results: Data for 85 patients with NeP-SD and 45 patients with NocP were analyzed to develop the SPDQ/SF-SPDQ. The SPDQ had sensitivity of 78.8% and specificity of 75.6% (AUC = 0.77). The SF-SPDQ had 82.4% sensitivity and 66.7% specificity (AUC = 0.75). In the multicenter study (n = 45), both tools had diagnostic utility almost comparable with that demonstrated at development: the SPDQ had sensitivity of 83.3% and specificity of 69.2%, with the SF-SPDQ having 86.2% sensitivity and 68.8% specificity. In the web-based survey (n = 500), while the SPDQ had slightly low sensitivity (74.0%), the SF-SPDQ maintained high sensitivity (84.4%), although specificity was relatively low (61.2%).
Conclusions: We developed the SPDQ and SF-SPDQ as valid screening tools for neuropathic pain caused by spinal disorders. Both have moderate utility as screening tools, with the SF-SPDQ perhaps being preferable for clinical use. However, physicians should be vigilant about possible false-positive diagnoses.