A mother’s recorded voice will wake a child and get him out of the room much faster than a standard smoke alarm, a randomized trial has found.

Researchers recruited 176 5- to 12-year-olds to test alarms. They taught the children a simulated escape procedure: Get out of bed at the alarm, walk to the door and leave the room.

They monitored the children with EEG electrodes until they entered a deep stage of sleep. Then they set off either a standard tone alarm or one of three versions of the mother’s recorded voice shouting instructions and the child’s name.

The study, in the Journal of Pediatrics, found that the tone alarm woke the children about 50 percent of the time, and it took them an average of nearly five minutes to get out of the room.

With the mother’s voice — shouting names, instructions or both — almost 90 percent of the children awoke and were out of the room in an average of less than 30 seconds.

The lead author, Dr. Gary Smith, director of the Center for Injury Research and Policy at Nationwide Children’s Hospital in Columbus, Ohio, wondered whether it had to be the mother’s voice or whether any human voice would work as well.

“What we really want,” he said, “is an alarm optimized for kids that will work for all age groups.”