The reason we need to know the role of the injury in the workers_ life is that any physical event creates both positive as well as negative openings for the emergence of problems just below the surface.
The end of a marriage can be delayed by injury. A debt can be forgiven by an injury. Mistakes at work can be overlooked due to injury. An extended leave from work can be provided by injury. The chance to spend more time with children or grandchildren can be permitted by injury. And the one most discussed, the chance for economic advancement can be met by injury.
However, there are even more subtle ways in which an injury is opportunistic: The individual who has felt oppressed by the responsibilities of life is now relieved of those pressures. Someone who has largely been ignored can now find attention and affection. Equally as important, someone who is avoidant by nature (prefers not to be around others), now has the privacy long needed.
When these gains (both primary and secondary) are being met (and for some injured workers multiple needs are concurrently met) returning him/her to work is complex if possible at all.
Thus, it is imperative to know whether there are subtle needs being met by the aftermath of injury. It is my opinion that a psychological exam is less about whether a patient has a specific disorder and more about what opportunities arise as a result of injury.