Question to the Department for Work and Pensions:

To ask the Secretary of State for Work and Pensions, whether he has made an estimate of the underpayment rate of personal independence payments for people with Parkinson's disease.

No such estimate has been made. Personal Independence Payment (PIP) is intended to act as a contribution towards the extra costs that arise from needs related to a long-term health condition or disability. Entitlement is assessed based on the needs arising from the health condition or disability, rather than a diagnosis of the health condition or disability itself. Any information that a claimant wishes to submit in support of their claim can be considered where that would help establish the needs arising.