Evidence-based practice is patient care based on research. It helps medical practitioners to make practical decisions based on the best available evidence. There are two types of sources you would want to look for: systematic reviews and clinical trials.
EBSCO Discovery portal is a gateway to over 60 databases that includes staple collections for nursing and medical research such as CINAHL Complete, Medline (PubMed), and PsycARTICLES. Elsevier journals and thousands of pertinent ebooks.