Generalizability vs. Transportability in Trials

[Lawrence_Lynn]

This is great. Consider discussing the two types of RCT. 1. The cause-integrity RCT(CIR) which have remained close to the original Bradford Hill method and 2. The cause-agnostic RCT (CAR).

Obviously there is a spectrum between the extreme of Bradford Hill CIR and the synthetic syndrome CAR.

The CAR provides the best example of Beautiful internal validity with no transportability.

Cause-Agnostic RCT (CAR)

Over on X there is a debate relevant causal inference vs RCT design. But what is an RCT? Since Bradford Hill’s landmark study we have seen the RCT morph into two species. So can we no longer speak of or debate RCTs as if they comprise a unified entity… a thing. There are CIRs (causal-integrity RCTs) for example the original Bradford Hill causal design, and CARs (causa-agnostic RCTs). a CIR conditions on a cause AND a covariate vector. a CAR conditions one or more thresholds (S=1) and …