Purpose Nonexperimental studies of treatment effectiveness provide an important
complement to randomized trials by including heterogeneous populations. Propensity …

Background: Few studies have investigated the diet quality of consumers of low-calorie-
sweetened (LCS) and calorie-sweetened (CS) beverages. Objective: The objective was to …

Background Theoretically, social climate and social networking which may affect attitudes,
motivations, and readiness towards quality improvement and rewards, influence the …

Systematic errors in pharmacoepidemiologic studies, particularly confounding, often
constitute serious concerns to inference on the causal relationship between drug use and …

Background In pharmacoepidemiology, the prescription preference-based instrumental
variables (IV) are often used with linear models to solve the endogeneity due to unobserved …

Classical regression model literature has generally assumed that measured and
unmeasured covariates are statistically independent. For many applications, this assumption …

Mendelian randomization studies use genotypes as instrumental variables to test for and
estimate the causal effects of modifiable risk factors on outcomes. Two-stage residual …

In health research and other fields, the observational data available to researchers often fall
short of the data that ideally would be available, due to the inherent limitations of study …

Mendelian randomization (MR) is becoming a popular approach to estimate the causal
effect of an exposure on an outcome overcoming limitations of observational epidemiology …

Observational studies are often in peril of unmeasured confounding. Instrumental variable
analysis is a method for controlling for unmeasured confounding. As yet, theory on …