Development and Validation of a Chinese Assessment Scale for the Primary Trigeminal Neuralgia Based on the Delphi Method

iObjective:/i To develop and validate an assessment scale for primary trigeminal neuralgia (PTN) that is suitable for Chinese patients’ clinical requirements and cultural background. iMethods:/i Descriptive study. (1) Construction of pre-scales: A pool of scale entries was prepared based on the common clinical features of PTN, the consensus of domestic experts, clinical diagnosis and treatment guidelines, and the reference of the international scale production process. Based on the Delphi method, 21 experts were invited to participate in two rounds of correspondence and pre-test revisions to develop the pre-scales. (2) Formation and validation of the preliminary version of the scale: A clinical investigation was conducted on 157 patients with PTN in the Pain Department of Shandong Provincial Hospital from March 20, 2024 to January 1, 2025. The entries were screened to form a preliminary version of the scale using the critical ratio method, correlation coefficient method, and discrete trend method. The scientific validity and feasibility of the scale were then assessed through reliability and validity tests, satisfaction measurements, and reflective tests. iResults:/i 147 patients with PTN completed the study. The positive coefficient of two rounds of expert correspondence was 100.0%, the authoritative coefficient was 0.927 and 0.957 (0.900), the Kendalls W coefficient was 0.227 and 0.421, respectively (all P0.001). The validity and reliability of the scale were positive, with Cronbachs α 0.870 (0.700), the content validity index 0.935 (0.900) for S-CVI and 0.810-1.000 (all≥0.780) for I-CVI respectively, the Kaiser-Meyer-Olkin (KMO) value 0.858 (0.600), and χ2=1 220.060 (P0.001) of Bartlett spherical test. The exploratory factor analysis extracted 3 common factors, with a cumulative variance contribution rate of 63.880% (＞50.000%) and factor loadings ranging between 0.533 and 0.905 for each entry. The correlation coefficient (r) between satisfaction and change before and after the treatment was 0.903. The scale demonstrated excellent responsiveness, as evidenced by a standardized response median (SRMed) of 2.71 and an effect size (ES) of 3.17 (both substantially exceeding the established benchmark of 0.80). The final scale consisted of 4 parts: the first part with 6 non-quantitative entries, the second part contained 4 dimensions and 20 quantitative entries, the third part contained 5 entries related to post-treatment evaluation, the fourth part was the overall satisfaction evaluation with 5 entries, and the third and fourth parts were for post-treatment only. iConclusion:/i The primary trigeminal neuralgia assessment scale has good reliability, validity, and applicability.