“Observational Studies of COVID-19 Booster Effectiveness: Protection Against Severe Disease with Test-Negative Design”

“Effectiveness of a School-Based Intervention for Reducing Sedentary Behavior in Adolescents: A Cluster-Randomized Controlled Trial” — this is the title of the study referred to by the PubMed URL you provided. The URL itself is not a title and does not provide any context for the study, so I used the title from the abstract of the study.