Type 2 diabetes is highly prevalent, and many adults, especially those not using insulin, struggle to reach HbA1c targets. This review aimed to evaluate the effect of self-monitoring blood glucose (SMBG) and continuous glucose monitoring (CGM) on glycaemic control in adults with type 2 diabetes. We searched MEDLINE, Cochrane Library, Embase, and Scopus from January 2014 to May 2025 for systematic reviews of randomized controlled trials enrolling adults with type 2 diabetes that evaluated SMBG or CGM versus no monitoring or SMBG, respectively. Fifteen systematic reviews comprising 81 unique studies and 23 657 participants were included. Reviews comparing SMBG with no monitoring demonstrated a modest but significant reduction in HbA1c (MD -0.23%, 95% CI -0.29 to -0.18; I2 = 21%). Reviews directly comparing CGM with SMBG showed greater HbA1c reduction with CGM (MD -0.29%, 95% CI -0.34 to -0.24; I2 = 0%). Subgroup analyses for SMBG indicated consistent benefits across follow-up duration, monitoring structure, and study quality, although heterogeneity was high in some comparisons. Subgroup analyses for CGM types found both isCGM/FGM (MD -0.27%, 95% CI -0.43 to -0.11) and rtCGM (MD -0.36%, 95% CI -0.45 to -0.27) superior to SMBG. These findings support glucose monitoring for optimizing glycaemic management and outcomes. Further investment in cost-effectiveness studies is warranted to assess broader implementation in this population.
Keywords: continuous glucose monitoring; glycaemic control; non‐insulin glucose‐lowering therapy; self‐monitoring of blood glucose; type 2 diabetes mellitus; umbrella review.
© 2025 John Wiley & Sons Ltd.