The current emphasis on comparative effectiveness research will provide practicing
physicians with increasing volumes of observational evidence about preventive care …

Abstract Real-world evidence (RWE), the understanding of treatment effectiveness in clinical
practice generated from longitudinal patient-level data from the routine operation of the …

A goal of many health studies is to determine the causal effect of a treatment or intervention
on health outcomes. Often, it is not ethically or practically possible to conduct a perfectly …

Regulators consider randomized controlled trials (RCTs) as the gold standard for evaluating
the safety and effectiveness of medications, but their costs, duration, and limited …

Noncausal associations between exposures and outcomes are a threat to validity of causal
inference in observational studies. Many techniques have been developed for study design …

Background Among the large number of cohort studies that employ propensity score
matching, most match patients 1: 1. Increasing the matching ratio is thought to improve …

Objective To estimate all cause mortality and cause specific mortality among patients taking
proton pump inhibitors (PPIs). Design Longitudinal observational cohort study. Setting US …

The use of instrumental variable (IV) methods is attractive because, even in the presence of
unmeasured confounding, such methods may consistently estimate the average causal …

ABSTRACT I review recent work in the statistics literature on instrumental variables methods
from an econometrics perspective. I discuss some of the older, economic, applications …

Confounding by indication poses a significant threat to the validity of nonexperimental
studies assessing effectiveness and safety of medical interventions. While no different from …