Psychometric analysis of the adult separation anxiety symptom questionnaire: Item functioning and invariance across gender and time.

The Adult Separation Anxiety Symptom Questionnaire (ASA-27) is the most widely used self-report assessment of adult separation anxiety (ASA). Despite its widespread use, relatively little is known about its psychometric properties, specifically whether it is unidimensional, its degree of precision (or information) across latent levels of ASA, the functioning of individual items in general and of -derived versus non--derived items in particular, and whether the measure is invariant across gender and time. We addressed these issues in a sample of 509 adult women and 407 adult men from the local community participating in a longitudinal study of temperament and psychopathology in children. Two items from the ASA-27 were removed so that the measure met the item response theory (IRT) assumption of unidimensionality. Findings from a graded response model for categorical items suggested that the ASA-27 assesses ASA most reliably at moderate to high levels and that the -derived items were more closely related to latent ASA than the non--derived items. Invariance tests employing single-factor confirmatory factor analysis models suggested that the measure is partially invariant across gender and time at the unique factor level, with fewer than 7% of parameters freed in both cases; this implies that the means and variances of the latent factors and differences in the observed responses are attributable to true differences in ASA. Future work should replicate these findings in a sample that includes individuals with a wider range of ASA severity and may consider removing additional items that provide little or redundant information. (PsycInfo Database Record (c) 2020 APA, all rights reserved).