Soumya MazumdarNerea AlmedaNasser BagheriMark DanielHossein Tabatabaei‐JafariGweneth LeighDiego Diaz MilanesLuis Salvador‐Carulla2026-03-222026-03-22202510.1136/bmjopen-2024-092657https://doi.org/10.1136/bmjopen-2024-092657https://andeanlibrary.org/handle/123456789/78450This umbrella review highlights the significant association between HbA1c and key health risk factors underscoring the importance of observational studies, highlighting their ability to capture real-world conditions and complex interactions. While in agreement with existing study designs, this review provides convergent evidence of the critical role of HRBs in managing HbA1c levels.enMedicineObservational studyMental healthPublic healthPsychiatryRisk assessmentEpidemiologyAssociation (psychology)MEDLINERisk factorarticle