|
| First author | Year | Country | Study design | Time period | Case source | Comparison | Estimates and 95% CI | Study quality |
| Unadjusted | Adjusted |
|
| Libby | 2009 | UK | Cohort (PB) | 1994-2003 | The resident population of Tayside Health Board | Metformin vs. nonmetformin | 0.49 (0.32-0.74) | 0.70 (0.43-1.15) | 8 |
| Lai | 2012 | Taiwan, China | Cohort (PB) | 2000-2008 | National Health Research Institutes in Taiwan | Metformin vs. nonmetformin | 0.43 (0.29-0.63) | 0.55 (0.37-0.82) | 7 |
| Ruiter | 2012 | Netherlands | Cohort (HB) | 1998-2008 | PHARMO Record Linkage System | Metformin vs. Sul | NA | 0.87 (0.84-0.91) | 7 |
| Neumann | 2012 | France | Cohort (PB) | 2006-2009 | French national health insurance information | Metformin vs. nonmetformin | NA | 0.88 (0.84-0.92) | 7 |
| Mazzone | 2012 | USA | Case-control (HB) | 2001-2011 | Cleveland Clinic Health System | Metformin vs. nonmetformin | NA | 0.48 (0.28-0.81) | 6 |
| Hsieh | 2012 | Taiwan, China | Case-control (PB) | 2000-2008 | Taiwan’s National Health Insurance Medical Claims Database | Metformin vs. Sul
Metformin vs. Ins | NA | 0.64 (0.45-0.9)
0.95 (0.46-1.95) | 7 |
| NA |
| Luo | 2012 | USA | Cohort (HB) | 1993-2010 | Women’s Health Initiative (WHI) study | Metformin vs. nonmetformin | NA | 1.32 (0.76-2.28) | 8 |
| Smiechowski | 2013 | Canada | Case-control (PB) | 1988-2009 | U.K. General Practice Research database | Metformin vs. nonmetformin | 0.97 (NA) | 0.94 (0.76-1.17) | 8 |
| Wang | 2013 | Taiwan, China | Cohort (PB) | 1998-2009 | National Health Insurance datasets | Metformin vs. nonmetformin | NA | 1.11 (0.94-1.47) | 7 |
| Tsilidis | 2014 | UK | Cohort (HB) | 1987-2010 | U.K. Clinical Practice Research Datalink | Metformin vs. Sul | NA | 0.96 (0.89-1.04) | 8 |
| Sakoda | 2015 | USA | Cohort (PB) | 1997-2012 | KPNC Diabetes Registry | Metformin vs. nonmetformin | NA | 1.02 (0.85-1.22) | 8 |
| Kowall | 2015 | Germany and the UK | Cohort (HB) | 1995-2013 | Disease Analyzer database | Metformin vs. Sul
Metformin vs. Ins | 0.81 (0.65-1.01) | 1.04 (0.82-1.31) | 7 |
| 1.28 (0.81-2.04) | 1.03 (0.64-1.64) |
| Chen | 2015 | Taiwan, China | Cohort (HB) | 1998-2008 | Longitudinal Health Insurance Dataset | Metformin vs. Sul
Metformin vs. Ins | 0.72 (0.58-0.88) | 0.74 (0.60-0.90) | 8 |
| 0.85 (0.61-1.18) | 0.95 (0.68-1.35) |
|
