Nudging a Nation — The Danish NUDGE Trial Concept

Randomized encouragement trial designs, where participants are randomly assigned to an opportunity or encouragement to receive treatment instead of to the treatment itself, can be useful for interventions where randomization to the intervention itself is deemed impossible or unethical. The nature of encouragement may itself influence the success of the trial. “Nudges” are interventions designed to influence decisions without restricting choice and may be utilized to improve randomized encouragement trials as well as in efforts to optimize real-world implementation of guideline-recommended interventions. Nudges are hypothesized to steer citizens toward appropriate health-related behavior and influence health care delivery through optimization of prescribing patterns, diagnostic testing, and compliance and adherence. Several prior randomized implementation trials have investigated the implementation of nudging into health care delivery; however, these have often been limited in geographical and demographic reach and results are mixed. To address evidence gaps, we are now introducing the Danish Nationwide Utilization of Danish Government Electronic Letter System (NUDGE) trial concept. Combining randomized encouragement trial designs with several advantages inherent in the Danish health care system, including universal free-of-charge health care, population-based health care registries, and comprehensive electronic communication systems, our trial concept enables testing of low-touch, potentially scalable nudges in a public health messaging context on a nationwide level. The concept may be applied across numerous populations and study aims. Future findings may inform health care policy decisions on a global level.