An instrument manipulates a treatment that it does not entirely control, but the instrument affects the outcome only indirectly through its manipulation of the treatment. The idealized prototype is ...

We draw attention to two problems associated with the use of instrumental variables (IV), the importance of which for empirical work has not been fully appreciated. First, the use of instruments that ...

Nonparametric instrumental variable (NPIV) estimation is a cutting‐edge methodological framework employed to uncover causal relationships in the presence of endogenous regressors, without imposing ...

In the article that accompanies this editorial, Lu et al 5 conducted a systematic review on the use of instrumental variable (IV) methods in oncology comparative effectiveness research. The main ...

“LIKE elaborately plumed birds…we preen and strut and display our t-values.” That was Edward Leamer's uncharitable description of his profession in 1983. Mr Leamer, an economist at the University of ...

Causal Inference in Oncology Comparative Effectiveness Research Using Observational Data: Are Instrumental Variables Underutilized? The following represents disclosure information provided by authors ...