Subsidised MRIs would be available at the Queen Elizabeth Hospital under the plan, after Labor earlier promised a rebatable MRI licence at Mount Barker.

"The people who benefit most from having their services close to home, accessible and affordable are the most vulnerable members of our society," Mr Butler said on Monday.

"Low-income families, older Australians, the chronically ill and people with complex medical needs in the western suburbs suffered most from the lack of MRI services in the west."

Labor's health spokeswoman Catherine King said residents of Adelaide's western suburbs face the sixth-longest wait times in the country for MRI scan specialist referrals.

"The region has half as many MRI licences per capita as other locations," she said.

MRI scans are used to diagnose soft tissue conditions including tumours and cancer, but only attract a rebate if they are performed on a machine with a licence.

Australian Associated Press