Toward standardized continuous glucose monitoring validation: lessons from the Sinocare iCan i3 accuracy study

Continuous glucose monitoring (CGM) has transformed diabetes management by providing real-time glucose measurements and supporting improved glycemic control. Consequently, the methodological quality of CGM accuracy studies has become increasingly important for clinicians, regulatory agencies, and healthcare decision-makers. The recent real-world evaluation of the Sinocare iCan i3 CGM system provides valuable evidence regarding device performance under routine clinical conditions. However, several methodological aspects warrant further consideration before the reported findings can be generalized to clinical practice. This perspective critically examines key aspects of CGM validation, including study design, selection of the reference glucose measurement, statistical methodology, temporal pairing strategies, sensor survival analysis, potential sponsorship-related bias, and interpretation of clinical accuracy metrics. We also discuss additional methodological considerations that were not fully addressed in the original publication, including uncertainty estimation, subgroup analyses, longitudinal sensor performance, missing-data mechanisms, and reproducibility assessment. Finally, we propose recommendations aimed at improving the methodological rigor of future real-world CGM validation studies and facilitating meaningful comparisons across CGM technologies.