Minister Edwin Poots said spending millions of pounds on consultancy work would help save money in the long run.
Ernst and Young has received an initial payment of around £600,000 to draw up local population plans.
The firm will provide information such as the number of adults, children and admissions to local hospitals.
Last year, the review team said the number of acute hospitals in Northern Ireland will probably have to be cut from 10 to five.
Such a move would not necessarily mean closing five hospitals, but they would lose A&E services and emergency surgery provision.
The review also recommended that much greater emphasis should be placed on treating people in their own homes and in the community.