While devastating for severely afflicted children and their families, autism has long been assumed to be relatively uncommon, appearing in perhaps 1% of all kids. But that figure was a rough estimate at best, based largely on the population of children who have already received a diagnosis of the disorder. Discovering the true prevalence of autism would require a large-scale study of an entire population–not just those who showed up at a doctor’s office. That’s exactly what a team of U.S. and South Korean researchers, led by Dr. Young Shin Kim at Yale School of Medicine, did in a six-year research project–with startling results. The researchers sought to screen every child age 7 to 12 in the Ilsan district of Goyang, South Korea. In their sample of 55,266 children, scientists found that the rate of autism spectrum disorders was 2.64%. That’s one case for every 38 kids, a rate much higher than the 1-in-110 estimate in the U.S. While those numbers sound scary, the results don’t mean there has been a sudden spike in autism. Rather, they simply reflect a more comprehensive collection of data. “These children didn’t just show up overnight,” Kim says. “They have been there all along. We just didn’t count them.” To ensure that they identified every case, Kim’s team sent a 27-item questionnaire to all the parents and teachers of elementary-school children in Ilsan. The questions were designed to flag kids with potential social or developmental delays typical of ASD. Those children were then evaluated for a possible diagnosis. Most cases of ASD caught by the study were among students in regular schools who had not been previously treated for mental-health problems; they were mostly high-functioning children. “Now we know there are kids with social problems who are not being treated, and we know how to help them,” says Kim. Better screening means earlier treatment and fewer kids who slip through the cracks. BRAIN INJURY Rating the Safety of Football Helmets Concussions have become a major problem for football, from the high school level to the National Football League. Recent studies have shown that retired NFL players who suffered multiple concussions exhibited dementia-like brain damage associated with high rates of depression, suicidal tendencies and memory loss. Studies also show that former NFL players as a whole have higher than usual rates of Alzheimer’s disease. Yet there has been little regulation of the one piece of equipment meant to protect a player from concussion: the football helmet. Thanks to researchers at Virginia Tech, however, that’s beginning to change. A team of engineers put together a system to rate football helmets on their ability to reduce the risk of concussion. The scores–from zero to five stars–are based on eight years of data and the analysis of more than 1 million measured helmet impacts. The bad news is that just one helmet–the Riddell Revolution Speed–earned the top five-star grade, while the Riddell VSR4 helmet, which is used by many pro players, received a paltry one-star rating. ENERGY Dangers of Shale Gas Drilling