In theory, yes. But in practice, a diagnosis of Autism (for example) is evidence for PIP and assessors ask about it during the interview. Same with EHCP's: Local Authorities take an Autism diagnosis as evidence.

Autism Central, grounded in lived experience and supported by robust research evidence running by #AnnaFreud working with
@grrand-team.bsky.social
at @uclbrainscience.bsky.social
NEW #NHS commission to improve lives of autistic people of all ages and their families. www.autismcentral.org.uk

Is there population screening for dementia in the US? In the UK this is the official line. The government agency for screening launched a consultation this year which has just closed, so potentially it could change.

view-health-screening-recommendations.service.gov.uk/dementia/