Healthcare of local people would have to be compromised following a proposed merger of the Otago and Southland district health boards, senior medical staff at Southland Hospital said.

Submissions on the proposal to combine the DHBs closed on Friday.

A letter opposing the move was written by the Senior Medical Staff Committee at Southland Hospital in Invercargill. The doctors expressed their concern about services being centralised to Dunedin and the loss of the board's advocacy for the people of Southland.

Committee chair Chuck Lueker said any merger must not mean health care being compromised.

Dr Lueker also said that Invercargill was a remote location and it was already difficult to recruit staff.

Association of Salaried Medical Specialists Otago representative Dr Chris Wisely said, "I think down south there is always that concern, or fear, they will somehow get submerged into the bigger conglomerate."

Regionalising clinical services was 'not necessarily a bad thing', but clinical practice should be driving the process.

Referring to the difficulty faced while traveling between Otago and Southland, different doctors said they would be affected differently as more clinical services were regionalised.