Item response theory for the color-picture version of Boston naming test in a Chinese sample with neurodegenerative diseases.

Background: Although Boston Naming Test has been thoroughly validated at a global level, there is limited assessment of item-level properties using modern psychometric methods.

Objective: This study aimed to investigate the construct validity and item-level properties of the color-picture version of Boston Naming Test (CP-BNT) in a Chinese cohort with neurodegenerative diseases.

Methods: This retrospective study included 424 participants, consisting of 118 normal controls, 152 with Alzheimer's disease, 101 with primary progressive aphasia, and 53 with other neurodegenerative diseases. All participants underwent a comprehensive neuropsychological assessment that included the CP-BNT. Factor analysis and item response theory were conducted.

Results: The CP-BNT exhibits a multidimensional structure with three factors: Factor 1, consisting of nine items with moderate difficulty levels, demonstrated peak measurement function for mild anomia (the highest information value = 33.7, ability estimated value = -0.8, reliability = 0.97); Factor 2, comprising eleven items with lower difficulty levels, performed well in cases of mild to moderate anomia (the highest information value = 34.1, ability estimated value = -1.2, reliability = 0.97); and Factor 3, including ten items with higher difficulty levels, provided the most measurement information for normal naming (the highest information value = 9.9, ability estimated value = 0, reliability = 0.90). All items, except item igloo, showed good discrimination (discrimination parameter ranged from 5.46 to 1.15). Most items had a different difficulty position versus the original version, thereby generating a novel item sequence with an ascending difficulty hierarchy for Chinese samples.

Conclusions: These findings support that the CP-BNT has good validity, reliability, and cultural appropriateness in the Chinese context, improving its utility in clinical assessments and interventions.