Age Affects the Impact of Important Predictors on Mental Health Emergency Department Visits.

Visits to emergency departments (EDs) for pediatric mental health care have increased over the years. The likelihood of ED re-visit is greatest for older children; however, little is known about age-varying effects on ED visits/re-visits. This study used population-based administrative databases from Alberta, Canada, to investigate the association of predictors on mental health ED visit frequency by age for 27,947 children who presented at least once for mental health care from April 2002 to March 2011. A marginal regression model with age-varying effects for sex, geographic area, and socio-demographic group was fit. The impact of predictors depended on a child's age. Notably, older males had lower ED visit frequencies compared to females (age 15 adjusted hazard ratio [aHR] = 0.70, 95% confidence interval [CI] [0.65, 0.76]) than younger males (age 10 aHR = 1.83, 95% CI [1.50, 2.24]). Children with particular ages for some socio-demographic groups also showed higher ED frequencies than children from the non-subsidized group. The analysis revealed important age-varying effects on predictors of mental health ED visit frequency.