The Turkish Adult Strabismus Quality of Life Questionnaire (AS-20): A Psychometric Validation Study

Objectives: To translate the Adult Strabismus Quality of Life Questionnaire (AS-20) into Turkish and evaluate its reliability and validity in Turkish adult patients with strabismus. Materials and Methods: Adult patients diagnosed as having strabismus and followed at the pediatric ophthalmology and strabismus unit of a tertiary university hospital were consecutively recruited. Patients with previous strabismus surgery, cognitive impairment, or insufficient Turkish language proficiency were excluded. A group of 15 participants completed the questionnaire a second time after a 2-week interval to evaluate test-retest reliability. Results: A total of 111 adult patients (63.1% female) were included in the analysis. The mean age was 32.0±14.5 years, and exotropia was the most common deviation pattern (85.1%). Diplopia was present in 7.2% of participants. The Turkish AS-20 demonstrated good internal consistency, with a total Cronbach's alpha of 0.874. The psychosocial subscale showed a Cronbach's alpha of 0.862, and the functional subscale demonstrated a Cronbach's alpha of 0.822, indicating good reliability. Test-retest reliability analysis demonstrated excellent temporal stability for the psychosocial subscale, the functional subscale, and the total score (p<0.001). Conclusion: The Turkish version of the AS-20 is a reliable and valid instrument for assessing strabismus-specific quality of life, demonstrating good internal consistency, high temporal stability, and applicability in both clinical practice and research settings.