The Conners scale can be used to screen children and adults for ADHD. However, research is mixed on its effectiveness. Regardless, it should not be the only assessment used when diagnosing ADHD.

The Kinsey Scale is one of the most widely used tools to describe sexual orientation, but it has several limitations that can't be ignored. Here, we break it down.

China's government is building what it calls a "social credit system" to track individual behavior and assign ratings to citizens. Here's how it will work. Video: Menglin Huang. Photo: Dave Tacon ...