Stable age pattern supports role of development in unintentional childhood poisoning

Objective: To investigate if child development has a role in unintentional poisoning, by describing the pattern of hospitalization due to unintentional poisoning in children aged 0-4 years in New South Wales by single year of age and then assessing the stability of the age-specific pattern found when analyzed by sex, remoteness of residence, and socioeconomic status. Design: Retrospective descriptive study. Setting: New South Wales hospitals from 1994 to 2005. Participants: Children aged 0-4 years in the New South Wales Department of Health Inpatient Statistics Collection. Main exposure: Hospitalization due to unintentional poisoning. Main outcome measures: Hospitalization rates by single year of age and single year of age by three covariates: sex, remoteness of residence, and socioeconomic status. Results: Children aged 1-3 years had the highest rates of hospitalization due to unintentional poisoning, and this pattern persisted over time. The same age-specific pattern was seen for both boys and girls, but rates were significantly higher for boys than girls at age 3 years (RR=1.46, 95% CI 1.31 to 1.62). The age-specific pattern persisted when the covariates remoteness of residence and socioeconomic status were controlled for. Conclusion: The age-specific pattern of hospitalization for unintentional poisoning by single year of age was found to be stable when analyzed over time and by sex, remoteness of residence, and socioeconomic status. This finding provides strong evidence for the role of a child's development in an unintentional poisoning event.