Metformin questioned for type 2

French researchers have flagged serious methodological flaws in a key study backing metformin as a first-line treatment for type 2 diabetes.

The UK Prospective Diabetes Study (UKPDS 34) published in 1998 found patients taking metformin and a sulfonylurea had a reduction in 10-year mortality from any cause and fewer myocardial infarctions compared with sulfonylureas only.

However, the researchers say the results