testing sites for 16 year olds(uk)

Does anyone know of any sites like usertesting which accept 16 year olds? I've tried my best to look for some but all say you must be 18 even though in the uk legally you're considered an adult at 16 anyways. I know there are sites like swagbucks but I mean actual testing sites where you get paid a decent amount per test. Any help would be appreciated.