RWE

Real world evidence must be considered as a complement of randomized controlled trials (RCT). An RCT is always considered higher in the evidence ladder. Most of the time real world study are done prospectively.

Even though real-world evidence studies have lower evidential value than RCT, some techniques can be used in order to mimic RCT. One such technique is propensity score method.

These methods allow to estimate in which treatment arm the subject would have been assigned in an RCT. This is estimated based on his baseline characteristics.

In an RCT the hypotheses testing is done in a double blinded setting. This ensures that the subjects have an equal chance of being assigned to one treatment arm or another. This is done to minimize bias.

RWE study can complement RCT study. It can fill some gaps left by RCT. For example, in a RCT the subjects that populate the study must pass the inclusion and exclusion criteria. This is not the case in an RWE study. But RWE can have some fault even if it used in that goal. For example, an explicit effort must be made in order to maintain electronic data record for retrospectivity.