Evidence Based Medicine Lecture PDF

Evidence Based Medicine  Evidence Based Medicine Evidence-based medicine (EBM) refers to the application of the best available research to clinical care, which requires the integration of evidence with clinical expertise and patient values.  Evidence-based medicine (EBM) uses the...

Evidence Based Medicine  Evidence Based Medicine Evidence-based medicine (EBM) refers to the application of the best available research to clinical care, which requires the integration of evidence with clinical expertise and patient values.  Evidence-based medicine (EBM) uses the scientific method to organize and apply current data to improve healthcare decisions. Thus, the best available science is combined with the healthcare professional's clinical experience and the patient's values to arrive at the best medical decision for the patient.  Steps of EBM There are 5 main steps for applying EBM to clinical practice: 1- Defining a clinically relevant question 2- Searching for the best evidence 3- Critically appraising the evidence 4- Applying the evidence 5- Evaluating the performance of EBM Why is EBM important  Health care personnel must use their clinical skills and prior experience to : 1- rapidly identify each patient’s unique clinical situation 2- applying the evidence tailored to the individual’s risks versus benefits of potential interventions. This results in a process of shared decision making, in which the patient’s values, circumstances, and setting dictate the best care.  EBM starts with a clinical question. The clinical question is an issue that the healthcare provider addresses with the patient. After the clinical question is formulated, relevant scientific evidence is sought, which relates to the clinical question. Scientific evidence includes study outcomes and opinions. Not all data has the same strength.  Recommendations from an expert are not as strong as the results of a well-conducted study, which is not as good as those of a set of well-conducted studies. Thus in evidence-based medicine, the levels of evidence or data should be graded according to their relative strength. Stronger evidence should be given more weight when making clinical decisions.  The evidence is commonly stratified into six different levels: Level IA evidence is obtained from a meta- analysis of multiple well-conducted and well- designed randomized trials.  Level IB evidence is obtained from a single well-conducted and well-designed randomized controlled trial. When well-designed and well-conducted, the randomized controlled study is a gold standard for clinical medicine.  Level IIA evidence is from at least one well- designed, executed, non-randomized controlled study. When randomization does not occur, there may be more bias introduced into the study.  Level IIB evidence is from at least one well- designed case-control or cohort study. A randomized controlled study cannot effectively or ethically study all clinical questions.  Level III evidence is from at least one non- experimental study. Typically, it would include case series, not well-designed case-control or cohort studies. Level IV includes expert opinions from respected authorities on the subject based on their clinical experience.  clinicians using evidence-based medicine must put all of the information in the context of the patient's values or preferences. The patient's values or preferences may conflict with some of the possible options. Even strong evidence supporting a specific treatment may not be compatible with the patient's preferences, and thus, the clinician may not recommend the treatment to the patient.  Also, the treatment might not apply to the specific patient. As an example, a patient may have a particular form of cancer. Level IA evidence may suggest life expectancy can double from 8 to 16 months with chemotherapy. Chemotherapy has significant side effects. The patient may find those side effects not acceptable and elect not to pursue chemotherapy secondary to the specific patient's preferences and values.