Psychometric properties of the adult executive functioning inventory (ADEXI) in adults with attention-deficit/hyperactivity disorder (ADHD)

The Adult Executive Functioning Inventory (ADEXI) is a brief novel self-report questionnaire designed to assess executive functioning. The aim of this study was to evaluate the psychometric properties of its Italian version in adults with attention-deficit/hyperactivity disorder (ADHD). A clinical sample of 84 adults diagnosed with ADHD at a tertiary care center was recruited. Discriminant validity was examined with respect to 252 age- and sex-matched non-clinical controls and norms extracted from a large epidemiological survey. Good internal consistency was observed for both the total score (Cronbach's α = 0.857) and subscale scores (α = 0.731-0.825). Both one- and two-factor structures showed acceptable fit. Convergent validity was supported by moderate correlations with self-reported ADHD symptoms measured by the ASRS-v1.1 Part A (r = 0.422-0.502), while only weak correlations were found with informant-reported executive impairments on the BRIEF-A (r = 0.231-0.237). Significant differences between participants with ADHD and non-clinical controls were observed. ADEXI total score best identified participants with ADHD using a cutoff ≥ 34, with accuracy = 89.6%, sensitivity = 92.9%, and specificity = 88.5%. ADEXI total scores converted in T-scores based on normative data revealed a prevalence of at least mild executive impairment (T-score ≥ 60) of 86.9% in the clinical sample, while two-thirds showed severe executive impairment (T-score ≥ 70; 66.7%). In conclusion, the ADEXI could be considered a useful instrument to screen for executive functioning impairments among the general population and a promising tool to stratify the severity of self-reported executive impairment across different clinical samples.