Advantages and disadvantages of observational study using real world data

Abstract

In evidence-based medicine since 1990’s, randomized controlled trials (RCTs) have been regarded as the most valuable clinical studies. However, treatment efficacy in RCTs is not always observed in clinical settings in the real world. Large-scale real-world data (RWD) is very useful to confirm clinical effectiveness of treatments in the real world, which RCTs have suggested. Observational studies using RWD are very susceptible to various biases. To control these biases, scientists should use appropriate methods, including propensity score method and instrumental variable method.