OBJECTIVES: To determine whether delirium prevention interventions reduce the risk of falls among older hospitalised patients. METHODS: A systematic search of health-care databases was undertaken. Given the frequency of small sample sized trials, a trial sequential meta-analysis was conducted to present estimate summary effects to date. A Bayesian approach was used to estimate the posterior probability of the delirium prevention interventions reducing falls risk by various clinically relevant levels. RESULTS: Five randomised controlled trials were included in our final meta-analysis. There was a 43% reduction in the risk of falls among participants in the delirium prevention intervention arm, compared to the control; however, confidence intervals were wide (RE RR = 0.57, 95% CI 0.32; 1.00, p = 0.05). This result was found to be statistically significant, according to traditional significance levels (z > 1.96) and the more conservative trial sequential analysis monitoring boundaries. The posterior probabilities of the delirium prevention intervention reducing the risk of falls by 10%, 20% and 30% were 0.86, 0.63 and 0.29 respectively. CONCLUSIONS: The results of this systematic review and trial sequential meta-analysis suggest that delirium prevention trials may reduce the risk of in-hospital falls among older patients by 43%. However, despite significant risk reduction found upon meta-analysis, the variation among study populations and intervention components raised questions around its application in clinical practice. Further research is required to investigate what the necessary components of a multifactorial intervention are to reduce both delirium and fall incidence among older adult in-patients.