A board report says Holdem, aged in his late 50s, has a "lifelong personality disorder with low intelligence".
In 2007, he was assessed by a psychologist, who found: "Mr Holdem probably has had more treatment for his sexual offending than almost any other offender of this type, with little apparent gain."
Holdem was eligible for parole in October 1996 and has now been in prison 30 years.
Further psychological reports were given to the board in 2013 and 2015. They revealed Holden had twice completed a programme for child sex offenders.
"But his response to such intensive treatment was insufficient to warrant consideration of his safe management in the community," the board says.
In 2012 and 2013 he had one-on-one psychological counselling session, but a report from those found he had "only superficial understanding" of what led him to commit sexual and violent crimes.
A further report in 2016 was criticised by Holdem and his lawyer, who isn't named in the report, because nobody met with Holdem.
He now wishes to again be assessed and also has treatments in mind, although Holden continues to accept he is not ready yet for release.
"That is obvious," the board report says.
It also found it was "premature" and "unrealistic" for Holdem to be considered for temporary release.
"He is a long way from being a realistic candidate for parole as [he] is an undue risk."
The board will see him again in December to decide if it should issue a postponement order, meaning they wouldn't have to consider Holdem for release again for another five years.
After abducting Louisa Damodran, Holdem drove to the Waimakariri River, north of Christchurch, where he strangled her and threw her in the river.
Her body was found weeks later.
Louisa's mother, Aynsley Harwood, told the Herald in 2007 that Holdem was driven to hurt children and prison was the only place for him.
"He will just have to stay there, otherwise children are in danger. It's the responsibility of every New Zealander to make sure people like Peter Holdem don't go around hurting children. I personally feel Louisa would have wanted to protect other children."
