BACKGROUND: The risk of early reattendance after discharge has been proposed as a performance indicator for emergency departments (EDs), but is not uniform in all patients. Those individuals at the highest risk of reattendance may benefit from an intense intervention to reduce this risk, and our objective was to test this hypothesis in a clinical trial. METHODS: A randomized-controlled trial was conducted in the EDs of two hospitals. Very high-risk adults aged 65 years and older, identified using a validated risk-prediction nomogram and being discharged from ED, were randomized to receive a postdischarge patient-centred intervention or standard care. The intervention focused on identifying and supporting patients to address risk factors for future hospital presentation. The primary outcome measure was any unplanned ED reattendance within 28 days. Secondary outcomes included 28-day and 1-year hospital usage, institutionalization and death. RESULTS: We enrolled 164 patients, 82 in each study arm. There was an 8% absolute (95% confidence interval: −7–20) and a 20% relative risk reduction for an intervention patient making an unplanned ED reattendance within 28 days. This difference was not statistically significant (P=0.26). CONCLUSION: This postdischarge intervention was associated with only small and nonsignificant reductions in ED reattendance.