Ali
YOUNESS

My thesis focuses on the study of response shift (RS) in longitudinal self-reported outcome (SRO) studies. I am developing an innovative
methodology to analyze this phenomenon at the item level of questionnaires, considering temporal continuity and the heterogeneity of RS trajectories. This approach aims to improve the reliability of longitudinal change estimates in SROs by accounting for individual variations in how RS influences item perception. By exploring the relationship between adaptation trajectories and RS following major events like the COVID-19 pandemic, I apply my methodology to real data on anxiety and depression among healthcare workers in cancer treatment centers. Finally, I work to promote accurate interpretation of RS results and their impact by developing knowledge transfer resources for researchers, patients, and clinicians.