Background Although effective when used correctly, child restraint systems (CRS) are commonly misused. Caregivers must make accurate judgements about the quality of their CRS installations, but there is little research on the psychological, technological, or contextual factors that might influence these judgements. Methods Seventy-five caregivers were observed installing a CRS into a vehicle and completed self-report surveys measuring risk appraisals, previous utilisation of CRS resources, task difficulty, and confidence that the CRS was installed correctly. Results Approximately 30% of caregivers installed the CRS inaccurately and insecurely, but reported that it was correctly installed. Predictors of confidence were ease of use (β=0.47) and exposure to CRS resources (β-0.34). Installation errors and CRS security were unrelated to caregivers' confidence. Conclusions An interdisciplinary approach is needed to understand factors influencing caregivers' judgements about their installations, optimise channels to connect caregivers to CRS resources, and to design safety technologies in light of these findings.