Sexual-abuse survivors feel "betrayed" that research they have helped develop has been used to tighten access to ACC counselling services.
ACC has changed access to counselling services, requiring greater proof that claimants have a diagnosis showing a mental injury caused by sexual abuse.
A review of progress after 16 counselling sessions is also required.
The ACC changes were partly influenced by 2008 Massey University research that included surveys and interviews with sexual-abuse survivors.
The 16-session review was developed using the Massey research.
A Christchurch sexual-abuse survivor, who was interviewed for the research, said he felt "double-crossed" by the way it was used by ACC.
The 49-year-old man, who wished to remain anonymous, was sexually abused by a cousin during childhood and received ACC counselling six years ago.
"They have double-crossed us. It is not right," he said.
"The research has been used against us ... We were never told it was going to be used by ACC."
He said he would be cautious about participating in future research.
Male Survivors of Sexual Abuse Trust manager Ken Clearwater had written to Prime Minister John Key expressing concerns about how the research was used.
"The research for male survivors of childhood sexual abuse is paramount for us and if the men we work with are not prepared to share their stories it could set us back several years," he wrote.
"The research has been used against victims and I just think that stinks," he said.
"The [victim] assessment is morally and ethically wrong. It is absolutely awful to put anyone through that process."
A second Christchurch man, who was sexually abused as a teenager and used ACC counselling services, said "no-one will get over this with just 16 sessions".
ACC senior medical adviser Peter Jansen said the review was not about cost-cutting, but about improving services.
He said the changes were not "set in stone" and could be adjusted for complex cases.
The 16-session review was established so ACC could make "an assessment of progress".
"I am sorry they feel betrayed, but there has clearly been a miscommunication," he said.
"We are not trying to withdraw things.
"The point of having this plan is to make the service better.
"We want to make better decisions about cover and then once someone is in therapy, ensure the best service is provided."
- The Press
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