Evidence-Based Medicine
Case-Control Study “A case-control study is designed to help determine if an exposure is associated with an outcome (i.e., disease or condition of interest). In theory, the case-control study can be described simply. First, identify the cases (a group known to...
Evidence-Based Medicine
“Diagnostic error is important because it is very common. Anchoring bias, also known as premature closure, is defined by the Agency for Healthcare Research and Quality as relying on an initial diagnostic impression despite subsequent information to the contrary....
Evidence-Based Medicine
Likelihood Ratio The Likelihood Ratio (LR) is the likelihood that a given test result would be expected in a patient with the target disorder compared to the likelihood that that same result would be expected in a patient without the target disorder. In other words,...
Evidence-Based Medicine
Odds ratio: Used only for retrospective studies (such as a case-control). It is a crude way to estimate the relative risk from retrospective data. Odds ratio = (Odds of exposure in disease group) / ( odds of exposure in control group). Odds ratio = A/ C divided by B/...
Evidence-Based Medicine
Relative risk (RR): Also called the risk ratio. The RR can be calculated only after you’ve done a prospective or experimental study. Relative risk or risk ratio (RR) is the ratio of the probability of an event occurring (for example, developing a disease, being...
Evidence-Based Medicine
Risk difference (or Attributable risk): The risk difference describes the actual difference in the observed risk of events between the experimental and the control interventions or between the exposed and non-exposed groups. Mathematically, it is risk difference =...
