Background Despite advances in prevention, injuries remain a leading cause of morbidity and mortality among children. Supervision is often cited as an important determinant of child safety.

Aims/Objectives/Purpose Assess the association between caregiver supervision and acute unintentional injury in young children.

Methods We interviewed parents of children ≤age 4 whose injuries required Emergency Department (ED) treatment or admission to the hospital, to collect information on supervision (proximity, attention, continuity) at the time of injury and 1 h before the injury). Hospital admission was a proxy for injury severity. Case-crossover analyses were conducted.

Results/Outcomes Interviews were completed by 222 participants; 50 (23%) were parents of children admitted to the hospital. For each dimension of supervision assessed, children admitted to the hospital were at higher risk of injury; proximity was associated with the highest risk. Compared to 1 h prior to injury, children were more likely to be beyond reach of their caregiver at the time of injury (OR 11.5, 95% CI 2.7 to 48.8 for children admitted to the hospital; OR 2.9, 95% CI 1.8 to 4.9 for children treated in the ED). Injury risk was highest for children with the least supervision; the magnitude of this association was higher for children admitted to the hospital (OR 11.5, 95% CI 2.7 to 48.8) than for children treated in the ED (OR 3.5, 95% CI 2.0 to 6.0).

Significance/Contribution to the Field Less vigilant supervision increases risk of serious injury in young children. Proximity may be the most important supervision dimension for assessing child injury risk.