Timing matters in (mis)identifying moderators and mediators of digital interventions for eating disorders: Commentary on McClure et al. (2023).

This commentary addresses the challenges in identifying consistent moderators and mediators of psychological treatments for eating disorders (EDs), as highlighted by McClure et al. (International Journal of Eating Disorders, 2023) in their systematic review. Specifically, we discuss the often-overlooked importance of temporal context (when an intervention is delivered), alongside sociodemographic and symptom type (for whom an intervention is delivered), in understanding and optimizing treatment engagement and effectiveness. We outline how individuals' fluctuating levels of motivation and receptivity across different "pivotal moments" in the help-seeking process-including initial outreach and self-screening, ongoing care engagement, and post-discharge-can dynamically impact interventions' relevance and impacts. We also overview how Just-In-Time Adaptive Interventions in digital mental health interventions can be harnessed to simultaneously consider "when" and "for whom" ED interventions can exert the greatest benefits. We conclude with several recommendations for conducting ED intervention and implementation research that integrate timing into support delivery and study design, enabling a deeper understanding of not just how and for whom, but when, ED interventions can be most effective.