Cluster randomised trials (CRTs) present unique ethical complexities for research ethics committees, participants, researchers and evidence users. In this design, whole social units (‘clusters’) such as hospitals, schools or entire communities are randomised to interventions. In addition, units of randomisation, intervention and outcome measurement differ within the one study. As a consequence, clearly determining research participants and establishing whose consent is required not only for randomisation and interventions but also data collection are correspondingly difficult.
This systematic review describes self-reported ethical practices in research conducted in Australia in which social units comprising Aboriginal and Torres Strait Islander people, their communities or services upon which they rely were randomised as whole clusters to trial interventions. To undertake this systematic review, we developed a study protocol and registered it prospectively on a public database (PROSPERO1 protocol CRD42018106463). Applying this protocol meant we could methodically identify all CRTs conducted in Aboriginal and Torres Strait Islander settings in Australia by finding their peer-reviewed study protocols or articles with main results reporting primary outcomes.