"This assessment will indicate to us what is doing well, what needs improvement and what our future needs may look like."
She said consultation with the public and stakeholders on the plan would take place when the two DHBs began the strategic planning process, probably in 2015.
Ms McKinnon said the plan was "no step towards merging DHBs".
"The plan allows us to plan for the future needs of MidCentral and Whanganui DHBs as autonomous DHBs."
WDHB collaborated on a number of services with MidCentral, Hawke's Bay, Wairarapa, Capital & Coast and Hutt Valley DHBs.
"With the growing cost of safe and available health services, collaboration and sustainability of our DHBs is paramount among all 20 DHBs in New Zealand," Ms McKinnon said.