If your toddler is prone to temper tantrums, how do you know if it's normal or means something more?

Researchers at Northwestern University have been studying preschool temper tantrums, trying to distinguish between typical misbehavior and early signs of possible mental health problems. They asked the parents of nearly 1,500 children ages three to five about their child's behavior. Using a newly developed questionnaire, they focused on the frequency and severity of the tantrums, the triggers and how well the kids were able to manage their anger.

While tantrums among the group were common, less than 10% of the children threw a daily fit. That relatively low percentage carried across girls and boys of all races and economic backgrounds.

The study's lead author says that discovering that temper tantrums were not rampant in this age group was an "ah ha" moment and that the data was a strong indicator that frequent tantrums are atypical and may be a sign of a deeper problem requiring intervention from mental health professionals.

The researchers are now fine-tuning this diagnostic tool to help doctors find the difference between a normal tantrum and troubling pattern of outbursts.