Scottish Public Pensions Agency (SPPA) administers the National Health Service Superannuation Scheme (Scotland) and is also responsible for scheme regulations. 

SPPA is responsible for all administrative tasks carried out in respect of current and past (deferred) members and NHS pensioners.

You can find the current NHS Superannuation Scheme rules on their Website.

Their Policy Branch is responsible for updating regulations in line with the policies determined by the Scottish Parliament and the UK Government.

The scheme is statutory and guaranteed by law, providing pensions and life assurance for those employed by the NHS in Scotland.