Have you heard about FOMO — "fear of missing out"? Most common among the under-30 crowd, it happens when someone feels nervous about not attending social events, like that awesome party everyone else enjoyed last weekend.

People have always been concerned about their social standing, but the explosion of social media has made FOMO a bigger issue, for everyone from middle schoolers newly toting smartphones to adults. Now researchers have developed a quiz to test just how fearful people are about missing out.

Among the questions the FOMO quiz asks are how often someone checks social media ("when eating breakfast?" "when eating lunch?" "in the 15 minutes before you go to sleep?") and how worried they feel when friends are hanging out without them. As the intro to the quiz puts it, "FOMO . . . is a relatively new concept where people are concerned that others may be having more fun and rewarding experiences than them. It is characterized as the desire to stay continually connected with what others are doing."