Tardive dyskinesia (TD) significantly impacts patients’ physical, cognitive, and psychosocial functioning. The Abnormal Involuntary Movement Scale (AIMS) is commonly used to evaluate TD treatment efficacy in clinical trials but does not capture the patient perspective on the impacts of uncontrolled movements. The Tardive Dyskinesia Impact Scale (TDIS) was developed as a patient-reported outcome measure to address this gap. This study aimed to assess the psychometric properties of the TDIS to determine if it is suitable for measuring the impact of TD from a patient’s perspective.

The qualitative results of the study indicated that the TDIS effectively captures the key impacts of TD as reported by patients and caregivers. Quantitative analysis revealed two underlying domains of the TDIS: physical and socioemotional. The TDIS demonstrated good construct validity, including responsiveness to treatment-related changes. The TDIS also showed a low correlation with the AIMS, indicating it provides unique information. Overall, the TDIS complements the AIMS and can be used to assess changes in TD impact over time, offering a more comprehensive evaluation of the disease’s effects.

Reference: Farber RH, Stull DE, Witherspoon B, et al. The Tardive Dyskinesia Impact Scale (TDIS), a novel patient-reported outcome measure in tardive dyskinesia: development and psychometric validation. J Patient Rep Outcomes. 2024;8(1):2. doi: 10.1186/s41687-023-00679-4.