There are three distinct stages of employment testing. One is for new hires, and that's what most people do because they want to know what they're getting when they hire somebody or they're hiring the next claimant. Second is testing your existing workers, because he might want to know if they can still perform the essential functions of their job safely. Third is to test people that are existing workers who've been injured.
You know, a lot of times people look at functional testing, they think about, well, when am I going to measure their job demands? It's at the end. No, you really should measure whether or not they're able to work at the first part so that you can continue to protect their job and keep them working rather than letting them be off work and maybe have to really work hard to get back to where they were without being productive.