YSQ-GeMS: Development of a Short Form of the Young Schema Questionnaire for Geriatric Mental Health Care Using Item Response Theory.

Schema therapy is effective for older adults with personality disorders, but the Young Schema Questionnaire (YSQ) may be too lengthy for use in geriatric mental health care. This study evaluated the construct validity of the YSQ-L2 in adults aged 35-97 years receiving residential or outpatient geriatric, psychiatric or medical care and developed a shorter form for this population. Data from 214 participants from Dutch nursing homes and outpatient services were analysed using Item Response Theory across 16 YSQ-L2 subscales. Each subscale was reduced to five items based on discrimination, difficulty, Differential Item Functioning for cognitive status and face validity. Most items showed adequate discrimination and coverage, whereas the Enmeshment scale had limited sensitivity and the Social Undesirability scale was excluded. The resulting 75-item YSQ-GeMS showed strong concordance with the original, providing a psychometrically robust and efficient tool for schema assessment in geriatric mental health care.