Objective Belt-positioning booster seat use (BPB) is an effective technology to prevent severe child injury in cases of car crash. However, in many countries, age-appropriate car restraint use for children aged 4 to 7 years old remains the lowest among all age groups. The aim of this study was to identify the main determinants of BPB use through a comprehensive approach.

Methods An ecological model was used to analyze individual, parent-child relationships, and neighborhood characteristics. Parents of children enrolled in the first and second grades completed a self-reported questionnaire (n=745). The data were subjected to multilevel modeling. The first level examined individual and parent-child relationship variables; in addition the second level tested between neighborhood variance.

Results According to parental self- reports, 56.6% of their children had used a BPB on each car trip during the previous month. The results indicated that the determinants positively related to BPB use were individual and parental; namely, the number of children in the family, the parents’ car seat belt use, parental knowledge of children’s car safety principles, and a highly authoritative parenting style. Children’s temperaments and parental supervision were not associated with BPB use. At the neighborhood level, a small difference was found between neighborhoods for BPB users compared to non-users.