Deduction for persons with disability permits certified residents to claim a higher deduction for severe disability upon filing prescribed medical certification. Resident individuals certified by a prescribed medical authority as a person with disability may claim a deduction when computing total income, with a larger deduction for persons certified as having severe disability; the claim requires filing the medical certificate in the prescribed form with the return, and where reassessment of the disability is required the deduction is disallowed for assessment years after certificate expiry unless a new certificate is obtained and furnished.