This is despite the government target to assess all claims by the beginning of April 2000 as part of implementing the supporting people proposals.
The research, carried out at the end of March, prompted responses from 73 housing associations with sheltered and/or supported housing - totalling nearly 76,000 units (27% of total RSL stock affected). Only 13% of housing benefit claims have been reviewed and a further 9% are under review.
The review of claimants is the first stage of the transitional housing benefit scheme which will continue until 2003. During this time, providers are expected to identify their housing and support costs separately.
The federation has written to ministers urging them to investigate why performance to date has been so slow, and to issue further instructions to local authorities, to encourage them to step up the review process.
Liz Potter, director of policy at the federation, said: 'These figures are alarming. If the supporting people fund is underestimated it will cause great hardship for older people and other vulnerable groups in the future.'