Accidents in which children die while stranded in hot cars may be more common than people realize, but the authors of a study probing the issue said there are numerous practical habits parents can adopt to ward off such tragedies.

The study from the Hospital for Sick Children concluded an average of one child a year dies across Canada after being trapped in an overheated vehicle, usually because a parent or caregiver forgot they were inside.

Forgetfulness played a role in four of the six deaths recorded between 2013 and 2018, according to the research published last month in Pediatrics and Child Health. The circumstances around a case too recent to be included in the research -- the death in May of a 16-month-old in Burnaby, B.C. -- are still under police investigation.

Study co-author Dr. Joelene Huber said such accidents can happen to anyone, but stressed that adopting new routines could prevent disaster.

"Never leave a child unattended in a motor vehicle, even for a minute," she said. "That should be a rule that you make for yourself: even if I forgot something in the house, I need to run back in the house with the child."

The majority of the deaths researchers studied involved incidents where a caregiver forgot to drop a child off at daycare.

This included the 2013 death of Maximus Huyskens, a Milton, Ont., toddler who died in the back seat of his grandmother's car one month shy of his second birthday.

Court heard the woman had collected her grandson from his mother's home, but mistakenly drove home after working a night shift without dropping him off at daycare as planned. She ultimately pleaded guilty to failing to provide the necessities of life and received a suspended sentence plus two years of probation at the joint recommendation of both the Crown and defence lawyers.

To avoid similar tragedies, Huber said parents should arrange to have child-care providers call and sound the alarm if one of their charges is unexpectedly absent.

She also suggested parents implement a few habits meant to guard against forgetfulness, such as placing their cellphones in the back seat of the car whenever a child is sitting there.

"You have to get your cellphone at some point, usually, so that's a good way to remember," she said.

Huber also urged parents to adopt the mantra of "look before you lock" and get in the habit of checking the back seat whenever they leave their vehicle regardless of whether they have a child with them at the time.

But she said the onus isn't all on the parents. The study suggests adding a section on the perils of hot cars to the Rourke Baby Record, which doctors refer to when teaching new parents about child development and safety.

Bystanders have a role to play, too, Huber said, noting people who spot children alone in hot cars should call 911 immediately even if the child seems alright.

Huber said a "greenhouse effect" takes place inside cars and can send the internal temperature soaring to deadly levels even when the outside temperature is a relatively cool 21 or 22 degrees Celsius.

The impact is especially dangerous for children, whose bodies are ill-equipped to regulate temperature and can quickly find themselves in danger if exposed to excess heat. Huber said children often experience delirium and then seizures before slipping into a coma or dying.

"If the child is in distress, we've talked to the police about this and they would recommend that you do whatever you can to get the child out of that car," Huber said.