Seclusion can be harmful for children and adolescents. Hence, all locations for secure residential youth care in the Netherlands are committed to reduce its use by implementing monitoring and... Show moreSeclusion can be harmful for children and adolescents. Hence, all locations for secure residential youth care in the Netherlands are committed to reduce its use by implementing monitoring and feedback as a seclusion reduction intervention. This study examined change over time in the use of seclusion in secure residential youth care in the Netherlands using a broad conceptualization of seclusion and by analyzing four variables (frequency, duration, room, reason). During two six months periods, seclusions were registered in 19 locations. Every month, all locations received feedback on the use of seclusion. Negative binomial mixed model analyses were used to investigate change over time in frequency and duration of seclusion. Logistic mixed model analyses were used to identify change over time in reason for use and type of room used for seclusion. Results showed that seclusion frequency significantly decreased (RR = 0.92, p < .001). Further, duration of placement in a seclusion room significantly increased (RR = 1.04, p < .001). This change was only significant in seclusion in response to aggression (RR = 1.06, p < .001). The results emphasize the need for future studies to examine reduction using a broad conceptualization of seclusion. Show less