Cluster headache (CH) is one of the most severe pain disorders and is associated with substantial disability. Unfortunately, patient-reported outcome measures (PROMs) specific to CH remain limited, despite their value for improving the assessment of disability in both clinical practice and research. The Cluster Headache Impact Questionnaire (CHIQ) is a short self-reported CH-specific patient-reported outcome measure to assess the current impact of CH. The aim of this study was to validate the French version of the CHIQ.

The CHIQ was translated from English into French using a forward–backward translation methodology. Patients diagnosed with episodic or chronic CH, according to the International Classification of Headache Disorders, 3rd edition (ICHD-3) criteria, were invited to complete the French version of the CHIQ, along with the Depression, Anxiety and Stress Scale 21 (DASS-21), the 12-item Short Form Health Survey (SF-12), and the Headache Impact Test-6 (HIT-6) once, then a second time 7 ± 2 days later. Cronbach's alpha was calculated to assess internal consistency, and test-retest reliability was evaluated using intraclass correlation coefficients (ICC).

Seventy-five patients were included in the validation cohort (mean age 44.5 ± 12.9 years, 34 women, 41 men). Of these, 44 patients presented with chronic CH and 31 suffered from episodic CH. The mean (±SD) global CHIQ score was 23.24 (±10.42). The CHIQ demonstrated high internal consistency as indicated by a Cronbach's alpha value of 0.92. The CHIQ score revealed a significant positive correlation with depression, anxiety and stress scores of the DASS-21 scale and HIT-6 scores, and a negative correlation with SF-12 scores. The test-retest reliability analysis of the French version of the CHIQ conducted on 40 patients, corresponding to active and stable patients (defined as patients experiencing attacks with a stable attack frequency), demonstrated good reliability (ICC = 0.83).

The French version of the CHIQ is a short, self-reported, CH-specific instrument for assessing current disability in patients with episodic and chronic CH.