Further research is needed to determine whether concussions affect the long-term health of players, rugby's international governing body says.
A three-year World Rugby study into the health effects of playing rugby has failed to find definitive links between the two.
More than 400 people participated in the study, including elite players, community rugby players and people who have not played any contact sport.
World Rugby chief medical officer Martin Raftery said it did not expect to get answers straight away.
"We were never going to answer the questions that people wanted answered. We went into that with our eyes wide open," he said.
"I think what's fair to say is it's actually helped us move along - not a long way but we've now got some good baseline data to move on with.
"There's also going to be some further analysis."
Dr Raftery said concussion education and prevention was at the top of World Rugby's agenda.