EBM is widely implemented in all decision making concerning health care. EBM is mostly based on metanalysis from studies that qualify for inclusion. Inclusion criteria may wary. However, you have not mention that EBM maybe fundamentally flawed because almost all paper that show not significance or negative date do not get published. The Cochrane library (http://www.cochrane.org) is the most trusted source of recommendations. Heurestics and logical thinking (mechanistic) can often yield much faster, cheaper and safer answer to biological questions than EBM based on metaanalysis imho.