Validation of a Self-Screening Questionnaire for Medication Overuse Headache (SSQ-MOH) in a Thai University-based Hospital Headache Clinic.

BACKGROUND: Medication-overuse headache (MOH) is a significant secondary headache that interferes with existing primary headache conditions, yet it is often an overlooked condition. This study aimed to develop and validate a user-friendly self-administered questionnaire to screen for MOH, to enhance early detection, an essential first step in the MOH care cascade in Thailand. MATERIALS AND METHODS: A Thai-language Self-Screening Questionnaire of MOH (SSQ-MOH) was developed to screen for MOH based on the International Classification of Headache Disorders, 3rd edition (ICHD-3), the Leeds Dependence Questionnaire, and the Severity of Dependence Scale. The questionnaire underwent iterative refinement through expert consultation with four headache specialists, patient feedback, and linguistic adjustments. The final questionnaire was launched, and data were collected from headache patients attending the specialized tertiary Headache Clinics, King Chulalongkorn Memorial Hospital, Bangkok, Thailand. Items in the questionnaire were selected and optimized to maximize sensitivity and specificity, using the final diagnosis made by headache specialists according to ICHD-3 criteria as the gold standard. Performance analysis-including sensitivity, specificity, predictive values, and the area under the receiver operating characteristic curve (AUC-ROC)-was conducted for each item individually. A combination of items was selected based on their individual AUC-ROC values. RESULTS: Among the 94 patients included (89.4% female; median [IQR] age: 38 [29.0-52.0] years), the most common primary headache disorder was migraine (87.2%, n = 82). MOH was diagnosed in 17 patients (18.1%). A combination of two items-"Q1: In the past month, have you experienced headache on at least 15 days?" and "Q2: In the past month, have you taken headache painkillers on at least 10 days?"-with both answered demonstrated the highest diagnostic accuracy, with a sensitivity of 88.3%, specificity of 90.9%, and an AUC-ROC of 0.90. CONCLUSION: The SSQ-MOH demonstrates high sensitivity and specificity in headache clinic settings, supporting its utility as an effective screening tool. Further validation in various clinical settings in Thailand and other languages is needed.