Table 2

Summary of pooled RRs with CI in the meta-analysis

AnalysisMeta-regressionNumber of studiesHR (95% CI)HeterogeneitySignificantModel
βPPI2(%)ZP
Overall 70.69 (0.54 to 0.87)0.00567.64.36<0.001Random
Comparison 0.6100.007
Metformin vs non-metformin50.61 (0.50 to 0.74)0.20931.84.92<0.001Fixed
Metformin vs sulfonylurea20.90 (0.83 to 0.97)0.5070.02.700.007Fixed
Geographic locations 0.4320.012
Western30.82 (0.69 to 0.98)0.07561.42.230.026Random
Asian40.44 (0.30 to 0.65)0.5070.04.08<0.001Fixed