"Disability," "disabled," or "incapacitated" means, with respect to qualification for an allowance payable to a surviving child, inability to engage in any substantial gainful occupation by reason of any physical or mental impairment that is determined by the board, on the basis of competent medical or psychiatric opinion, to be of permanent or extended and uncertain duration.
(Added by Stats. 1995, Ch. 379, Sec. 2.)