Sackett's Rules for Level of Evidence Studies Flashcards
types of studies in level 1
randomized controlled trials (RCTs)
meta-analyses of level 1 RCTs
examples of level 1
study that examines the difference in stroke occurrence in patients with atrial fibrillation given aspirin vs. apixaban (without knowing which they are being given) over a 10yr period
types of studies in level 2
prospective cohort studies
meta-analyses of cohort studies
level 2 examples
study that examines the rates of lung cancer in smokers and nonsmokers over a 30yr period
types of studies in level 3
retrospective cohort studies
case-control studies
level 3 examples
study that examines patients with diverticulitis and looks back at differences in diet between patients who were diagnosed with the condition and those who were not
types of studies level 4
case series
cross-sectional studies
level 4 examples
study that describes the BMI, HgbA1c, BP, and smoking exposure of patients with coronary artery disease
types of studies level 5
expert opinion
anecdotes
case reports
level 5 examples
a unique case report about a patient with a seizure disorder precipitated by a cephalosporin antibiotic
meta-analysis
compilation of findings form various studies examining a similar treatment or outcome
case-control
retrospective study that examines patients with an outcome against a control group to identify any exposures that contributed to said outcome
cross-sectional
a static, descriptive study that examines data from a patient group at a specific point in time
cohort - prospective
examine a group of patients and separates them by certain independent factors (exposures) to evaluate for an outcome over a certain span of time
cohort - retrospective
look backward in time at an exposure group vs a non exposure group to evaluate the risk of an exposure leading to an outcome
