IRB chief executive Brett Gosper believes the new scrum laws have made a positive impact during their first month of operation.
Criticism
Asked about Youngs' remarks about feeling more at risk, Gosper said there was no evidence that was the case.
He added: "We are not seeing anything that backs them up. I can understand some are feeling uncomfortable with the process of change as they have had their body position the same for the last 10 years and someone is saying 'now you have to change' and they probably feel a bit vulnerable.
"Certainly none of the early statistics is backing up there is a health risk but we will absolutely monitor that."
Gosper also defended the IRB's decision against Cockerill's criticism that they had merely created "a different kind of mess" in the scrum.
He said: "I read Richard Cockerill's statement and I got the feeling that, with great respect to his experience, he felt a bit irked that he wasn't personally involved in discussing the changes.
"We did consult widely with a broad array of scrum coaches at international level because we tend to dialogue with the unions and not the clubs - it's the unions who speak to the clubs, that's the protocol.
"I think he was a lone though obviously influential voice not accepting of the change and I don't think that's a general view."
