Validation and Test–Retest Reliability of the Cervicogenic Headache Severity Questionnaire (CeH-SeQ): A Patient-Reported Assessment Tool

Cervicogenic headache (CGH) represents a secondary headache disorder arising from cervical spine dysfunction, characterized by neck pain radiating to the head. Despite its prevalence, standardized and validated tools for assessing CGH severity remain limited. Objectives: To validate and assess the test-retest reliability of the Cervicogenic Headache Severity Questionnaire (CeH-SeQ), a patient-reported outcome measure designed to evaluate CGH severity. Methods: The CeH-SeQ was developed based on diagnostic criteria and clinical features of CGH. It includes two sections a diagnostic screening component and a severity measurement component. Content validity was evaluated using the Delphi method with 10 domain experts, and test-retest reliability was assessed in 30 participants with CGH. Statistical analysis was performed using Microsoft Excel. Results: The Scale-Content Validity Index (Average) was 0.82, while the Universal Agreement was 0.50. Among 32 items, 16 achieved universal agreement. Test-retest analysis revealed high reliability (Pearson's r = 0.91, ICC = 0.85, Kappa = 0.98, SEM = 5.37). The mean CeH-SeQ score improved from 76.48 (T1) to 81.32 (T2). The sample comprised 9 males and 17 females with a mean age of 35.57 years. Conclusions: The CeH-SeQ demonstrates strong reliability and satisfactory content validity, confirming its usefulness as a comprehensive and patient-centred tool for assessing CGH severity.