The Conclusive and Continuous Tool to Assess Severity and Improvement of Eating Disorders (CONTASI-ED): Development and Psychometric Properties

Background: Accurately assessing eating disorder (ED) severity and treatment progress is essential for effective intervention. The Comprehensive and Continuous Tool to Assess Severity and Improvement of Eating Disorders (CONTASI-ED) was developed to address limitations in existing assessments by incorporating behavioral, cognitive, and physiological markers. Objectives: This study aimed to examine the psychometric properties and sensitivity to symptom changes of the CONTASI-ED in a community-based clinical sample of women with ED. Methods: Participants were 58 females diagnosed with EDs and 10 healthy controls. The CONTASI-ED assessments were conducted over multiple time points in outpatient and intensive treatment settings. We examined reliability, validity, and sensitivity to treatment-related change. The CONTASI-ED scores were compared with EAT-26, and multivariable analyses explored the effects of body mass index (BMI), age, and post-traumatic stress disorder (PTSD) on symptom trajectories. Results: The CONTASI-ED demonstrated strong reliability, with test–retest correlations between 0.72 and 0.90 and inter-rater reliability of 0.68–0.95. The tool effectively distinguished ED patients from healthy controls (p < 0.001) and correlated strongly with EAT-26. Significant reductions in the CONTASI-ED scores over time (p < 0.001) reflected treatment-related improvements—although temporary score increases highlighted greater self-awareness and symptom disclosure. BMI, age, and PTSD significantly influenced symptom severity and treatment response. Conclusions: The CONTASI-ED demonstrated strong reliability and validity in distinguishing clinical and non-clinical cases and in tracking treatment-related changes. However, the findings are based on a relatively small, all-female sample, underscoring the need for further validation in more diverse populations.