In 2008, Gary Smith, a reserved, silver-haired pediatrician, began dropping cheerleaders on their heads. He and a colleague constructed a 15-foot-tall tripod at Smith’s research center in Columbus, Ohio, and dangled from its apex a 12-pound silver “head” stuffed with crash-test instruments. They dropped the head from varying heights onto dirt, grass, vinyl, concrete, blacktop, rubberized track, springy mats, and maple gym flooring. By measuring impact forces, they were able to calculate how far a cheerleader could fall onto each type of surface and still avoid cracking her skull.

Smith, who has been studying child injury for over 30 years and founded the Center for Injury Research and Policy in Columbus in 1999, was searching for a safer way for cheerleaders to perform their high-vaulting acrobatic stunts. “Cheer” has become the riskiest school sport for young women, with potentially disabling brain and spine injuries increasing fourfold since the 1980s.

But cheerleading is just one example of the hidden dangers children face. Injury is the biggest cause of death and disability for kids from one to 18. Falls, burns, road crashes, and other accidents claim more lives than cancer, infections, and birth anomalies combined. The problem goes beyond medicine’s ability to heal: The lower a family’s income, the more its children risk injury, both in the U.S. and globally. Smith and his colleagues have learned to focus on safer products and stronger regulatory standards—creating more protected environments, in other words, rather than making parents responsible for overseeing their kids in an unsafe world. Their approach has helped hundreds of thousands survive the hazards of childhood.

Injury is the biggest cause of death and disability for kids from one to 18. Falls, burns, road crashes, and other accidents claim more lives than cancer, infections, and birth anomalies combined.

Smith himself contracted polio as a child before vaccines reached his rural California hometown. He walks with crutches and leg braces, and became a doctor in part because of his childhood exposure to medicine. By age 30, he had earned five higher degrees from Stanford, the University of Southern California, and Johns Hopkins in biology, medicine, and public health, and was working as an emergency-room pediatrician. He began studying child injury in the early 1980s, just as a slew of public health campaigns and resulting regulatory changes started reshaping the landscape of childhood. In those days, smoke alarms, infant safety seats, bike helmets, stair gates, pool fences, childproof lids, and choking-hazard warnings were rare to non-existent, and seldom mandatory. The responsibility to protect children rested mainly with parents. And the per-capita child death rate was about 43 percent higher than it is today.

Take the baby walker. Many parents of five- to 15-month-olds bought these four-wheeled support frames which allowed infants to scoot about before they could walk. The problem was in older models babies could move too fast, and occasionally crashed into walls or tumbled down stairs. By the mid-1990s, walkers were landing an estimated 25,000 babies in the ER every year.

Faced with this and other dangers, “parents bought the myth of supervision,” Smith says: They believed that by increasing their vigilance, they could prevent injuries. But, says Smith, “they were wrong!” Based on studies by Smith and others, and pressure from consumer groups, the Consumer Product Safety Commission created new voluntary safety standards in 1997. Manufacturers redesigned walkers to be wider than most doors and to stop abruptly if they go over the edge of a step. Within 10 years injuries had declined by 95 percent. It took research, redesign, and regulation—not increased parental vigilance—to solve the problem.

In 1999, Smith brought these lessons to a broader audience when he helped found the child safety center in Ohio. The center’s dozen researchers have documented a horror show of everyday childhood dangers: knives, saws, snow shovels, microwaves, baby beds, portable pools, batteries (swallowed or lodged in orifices), many types of sports, slamming doors, toppling TVs, pedestrian mishaps; and falls down stairs, through windows, and off balconies. Their investigations have helped inspire campaigns for strengthened safety standards for products from drop-sided cribs to battery compartments.

In a recent study on household cleaners, Lara McKenzie, a behavioral scientist at the center, discovered that kids under six often swallow or squirt their eyes with cleaners from spray bottles. She and her team developed and patented a child-resistant spray bottle with a dual-action trigger, and are working to get the product onto the market. Smith himself is currently developing a more effective smoke alarm. In his experiments, the standard home units with their blaring buzz-tones fail to arouse most six- to 12-year-olds from a deep sleep. Smith and his colleagues are trying out more effective sounds, including mothers’ voices calling out their children’s names.

Smith acknowledges that low-income families—whose already higher injury risk is compounded by factors like crowding, run-down buildings, and missing stair gates and window guards—are less able to afford the newest and safest devices. But the entire public does benefit from improved traffic lights, safer bike lanes, and other outgrowths of child injury research. And innovations keep coming. Speakers at a recent international conference hosted by Smith’s organization described cleverly designed solar lanterns and sand-filled candle holders. These cheap devices are already preventing burns from the open-flame lighting so common in developing countries.

After Smith and his colleagues published their cheerleading study results, including those from the tripod tests, pressure mounted on states and national cheerleading groups to adopt stricter rules. Now a number of new rules are in place, including bans on high-flying stunts over hard surfaces. “Kids need to challenge themselves,” Smith maintains, whether they are toddling near a burning candle or cheering before a crowd. Exploring, failing, and trying again are all part of growing up, he adds. But the “price of failing shouldn’t be the price of your life or a permanent disability.”

This post originally appeared in the March/April 2014 issue of Pacific Standard as “The Myth of Supervision.” For more, subscribe to our print magazine.