A survey found that 40% of employees said they called in sick over the last year when they were perfectly healthy. Sort of surprising: A lot of those fakers are getting busted by their employers. The CareerBuilder survey found that 38% of employers checked up on a “sick” worker, and 26% said they had fired someone they discovered had given a fake excuse. So how are these not-really-sick employees getting caught? Social media. 43% of employers surveyed said they discovered an employee was lying about being sick after checking out their social media accounts.