OTTAWA -- A veterans group says auditor general Michael Ferguson's latest report clouds the most important issue when it comes to the increasing use of medical marijuana to treat injuries such as post-traumatic stress disorder.

Clayton Goodwin, of the Veterans Accountability Commission, one of a growing number of grassroots organizations, says last week's audit focused too narrowly on the rising cost of the program and not on the health benefits of switching from pharmaceuticals to medicinal pot.

He claims there are cost-savings associated with dropping prescription drugs, and would have preferred to see the report analyze that aspect.

"In the auditor general's report; he basically leaves out facts," Goodwin said at a media event on Parliament Hill on Monday. "He comes at it from the cost of medical marijuana. He has not said anything about the cost of pharmaceuticals."

Veterans who are taking part in the program should have been interviewed -- or at least consulted -- about changes in their quality of life after switching to medical marijuana as part of their therapy, said Goodwin.

"My anecdotal evidence from speaking with people in the community is an 80 per cent reduction in the use of pharmaceuticals," Goodwin added.

It would have been tough for Ferguson to measure some of the evidence Goodwin wants to see, because the audit said the veterans department does a poor job of tracking prescription drug usage.

The audit found the department did not have "an adequate process for evidence-based decisions related to its drug benefit list."

The committee that oversees the decisions could not provide proof that it had considered "veteran's needs, current health practices and policies, clinical research and cost-effectiveness" in coming up with the drug benefits list.

Ferguson's report urged the Trudeau government to get a grip on the marijuana program for injured ex-soldiers, which is expected to cost taxpayers $25 million this year.

He painted a picture of program out of control and said Veterans Affairs recognized years ago the need to contain the program by imposing a limit on how much the government is willing to pay per gram -- something federal officials have shied away from doing.

Three years ago there were 112 veterans taking prescribed pot at a cost of $408,000, but by the end of December 2015 some 1,320 ex-soldiers were enrolled at a cost of $12.1 million.

The Liberal government said it accepts Ferguson's report and Veterans Affairs Minister Kent Hehr has ordered a review of the policy. He said he intends to consult veterans and officials, something Goodwin welcomed.