Yes, QUALIFIED is a Scrabble word!

Letter values in Scrabble US: Q 10, U 1, A 1, L 1, I 1, F 4, I 1, E 1, D 2.

Is it a valid word?

QUALIFIED is a valid word in the official Scrabble dictionary (US), the UK Scrabble Dictionary and Words with Friends (ENABLE).

prove capable or fit; meet requirements
pronounce fit or able
make more specific
make fit or prepared
specify as a condition or requirement in a contract or agreement; make an express demand or provision in an agreement
describe or portray the character or the qualities or peculiarities of
add a modifier to a constituent

meeting the proper standards and requirements and training for an office or position or task
limited or restricted; not absolute
holding appropriate documentation and officially on record as qualified to perform a specified function or practice a specified skill
restricted in meaning; (as e.g. `man' in `a tall man')
contingent on something else

Also: measure up.

Not playable in Scrabble US: CHARACTERISE.