Reprint of: An introduction to effectiveness-implementation hybrid designs.

The traditional research pipeline that encourages a staged approach to moving an intervention from efficacy trials to the real world can take a long time. To address this issue, hybrid effectiveness-implementation designs were codified to promote examination of both effectiveness and implementation outcomes within a study. There are three types of hybrid designs and they vary based on their primary focus and the amount of emphasis on effectiveness versus implementation outcomes. A type 1 hybrid focuses primarily on the effectiveness outcomes of an intervention while exploring the "implementability" of the intervention. A type 2 hybrid has a dual focus on effectiveness and implementation outcomes; these designs allow for the simultaneous testing or piloting of implementation strategies during an effectiveness trial. A type 3 hybrid focuses primarily on implementation outcomes while also collecting effectiveness outcomes as they relate to uptake or fidelity of the intervention. This paper provides an introduction to these designs and describes each of the three types, design considerations, and examples for each.