Effects of an App-Based Intervention to Improve Awareness and Usage of Early Childhood Intervention Services During the COVID-19 Pandemic: Randomized Controlled Trial of the CoronabaBY Study from Germany.

: Young families experiencing high levels of psychosocial stress should be addressed at an early stage to counteract potential negative effects on the parents' and child's wellbeing. This became particularly relevant during the COVID-19 pandemic when especially families have been strained by restriction measures. Early Childhood Intervention services (ECI) can provide low-threshold support, to which access should be encouraged. : The randomized controlled trial of the CoronabaBY study with N = 1384 participants focuses on the effects of a newly developed app-based intervention on the awareness and usage of ECI services by young families with infants and toddlers during the COVID-19 pandemic in Germany. The analysis compares knowledge and usage rates of an intervention group (IG) and a waitlist control group (WCG) at three survey stages (pre-test, post-test and follow-up). : There was a significant increase in awareness of ECI services from pre-test to post-test in both the IG (15.2%) and WCG (10.7%) ( < 0.001), but the difference between the two groups was not significant. In contrast, the usage rate of further ECI services at post-test was significantly higher in the IG (12.1%) compared to the WCG (8.2%) (V = 0.060, = 0.012), especially in a subgroup of highly stressed parents. : Digital applications show potential to improve access to ECI services and should be continuously developed and evaluated to appropriately address young families and their needs.