What do Sean Penn and Robert F. Kennedy, Jr. have in common? They’re both wealthy celebrities pushing new documentaries that make dangerous, unproven claims about the causes of autism. The rate of autism diagnoses has indeed skyrocketed in the past 20 years from 1 in 10,000 to 1 in 68. However, as the Centers for Disease Control and Prevention (CDC) points out, a large (though not the only) factor in that dramatic jump is increased disease awareness and screening, including more in-school screenings and more medical professionals willing to label the condition. You diagnose zero percent of the cases you don’t test for. Read more.