A job analysis may only support the use of a few constructs.
This creates a few practical challenges:
(1) how do we score the measures? Do we combine scores or do we create a multiple hurdle approach?
If we are using an off-the-shelf measure of personality and are only using two of the big five dimensions, what do we tell the candidates? In the case of the NEO-PI, candidates would need to complete all of the items, but only 2/5ths of the items would be used.