Jim Clarken, Oxfam Ireland Chief Executive, said the worldwide organisation's review shows their commitment "to enforce a zero-tolerance approach" to sexual misconduct.
Asked about Evans's allegations, Oxfam said her work had spurred the organization into taking concrete steps to improve the way it deals with "safeguarding" issues.
He has apologised over the incident - but his interview published Friday was at odds with comments by the charity's global head who urged victims of abuse to come forward, and said that the exploitation was a stain that shames the charity.
British Development Minister Penny Mordaunt said the group has agreed not to bid for any new funding from Britain's government until London is satisfied the aid organization meets its "high standards".
'There are hundreds of good, courageous and compassionate people working for Oxfam around the world.
"We have doubled the number of people to four in our dedicated safeguarding team and we are in the process of recruiting two extra staff", Oxfam said in a satement.
"(But) the intensity and ferocity of the attacks makes you wonder, what did we do?
Mark Goldring, the Chief Executive of Oxfam, has lambasted the intensity of the criticism levied against his organisation over claims that its workers used prostitutes in Haiti.
Van Hauwermeiren, who has taken part in an internal enquiry at the British charity, said he told Oxfam he had engaged in "intimate relations some three times" at his home. I struggle to understand it.
UK-based Oxfam has been rocked by allegations that senior staff working in Haiti after the country's 2010 natural disaster faced misconduct allegations, including using prostitutes and downloading pornography.
"I think (her criticism) was very unbalanced, and ironically didn't give enough credit to the very work that she promoted", he told the paper.
The executive director of Oxfam, one of the leading worldwide relief organizations in the world, has apologized and asked forgiveness in the wake of allegations that a former director hired prostitutes in disaster zones.
The prostitution allegations were not passed to Haitian authorities at the time of the inquiry, but Oxfam said it had now passed on the names of the men involved.
In response, Oxfam on Friday said it would create a global database of accredited referees to crack down on forged or unreliable references from past or current employees.