"It only takes a couple of minutes and a few inches of water for a child to drown," senior author Dr. Gary Smith, director of the Center for Injury Research and Policy at Nationwide Children's Hospital in Columbus, Ohio, says in a statement.
"It is important for parents to realize that portable pools can be just as dangerous as in-ground pools."
Wading pools, inflatable pools and soft-sided, self-rising pools are popular inexpensive alternatives to in-ground pools or park visits, but the multiple layers of protection required by in-ground pools are either relatively high in cost or are not specifically designed for portable pools such as isolation fencing, safety covers, lockable or removable ladders and pool alarms, Smith says.
"Drowning prevention tools used for in-ground pools are often either too expensive or simply not available for portable pools," said Smith, who is also of the Ohio State University College of Medicine.
The study, scheduled to be published in the journal Pediatrics, finds 94 percent of the drownings involved children age 5 and younger and 73 percent of the drownings occurred in the child's own yard.
Celebrity Breakups and divorces of 2014 [PHOTOS]