Before you do anything to or for a patient, you need to be reasonably sure what you are about to do is the right thing to do. Knowing what is right is a complex issue!
Every patient is different and presents different challenges and even has their own opinion about what they want done for them. These opinions may be due to their culture, their past experience with health care, or their goals for their own health outcomes. An elderly patient newly diagnosed with cancer might choose a different course of treatment than a young patient with small children to care for.
Health care professionals need to be supportive of patients as they make these decisions by providing them with all the facts necessary to make informed decisions.
Often, interventions are decided on based on a professional's experience. If they have been in a similar situation before, and suspect a similar result, they can use this experience to select the best intervention. Reading an article or a book by a verified expert in the field can also provide ideas for intervention. Professional colleagues, peers, or experts in various fields are another source of knowledge when choosing an intervention.
The most common source of information when deciding on an intervention is best practice. Best practice consists of experiments where evidence has proven an intervention works--or does not work and should be avoided. Experiments like these are published in professional literature and can be access through library subscription databases. Your librarian can help you find the best articles for your needs.
Together these three factors, patient opinion, expertise/experience, and best practices, comprise Evidence Based Practice.