Denise Fisher of the Alberta Cheerleading Association says a dozen teams have pulled out of the group's championships next weekend due to a threat made against the mall in an online video.
The video purportedly came from the Al-Shabab group and urges Muslims to attack malls including the Mall of America in Minneapolis and the West Edmonton Mall.
Fisher says the cheer groups that have cancelled have done so with "a very heavy heart" after consulting with parents, coaches and athletes.
But she says other parents have called to express their confidence in police, who have given assurances that the mall remains safe.
Fisher says they've told her they don't want to let fear take away from the type of freedom Canadians enjoy.
"Fear is something that's very difficult to define. We have the reassurance of the Edmonton Police Service that the event is safe and the Alberta Cheerleading Association is relying on that authority as the way to make the decision to keep with the competition," Fisher said on Saturday.
"To say that a parent's fear for their child is ever irrational — I don't think I could ever say that. It's a parent's job to consider the welfare of their children and I know from many of the parents that I have spoken with, it's a very difficult decision for them."
The association's website says the mall's administration has confirmed "there will be significantly increased mall and police presence in the mall during the competition, although many will be plain-clothes officers."
It also says the cheerleading association has contracted some additional security of its own, and has been working with an independent company to have onsite first aid and to ensure that its response plans align with West Edmonton Mall's plans.
It says it cannot circulate internal documents such as lockdown procedures, as wide distribution could negate the benefits they provide. But it says coaches will get some of the information before the event.
The event promises to feature 3,200 athletes representing 180 teams from British Columbia to Ontario.
Fisher won't say which groups have decided not to come. She said ticket sales for the event, which starts March 6, have been good and that spectator support is expected to be solid.
She said many of the participating groups have been reassured.
"One of the things that they want to hear most is that we are monitoring this carefully and also that we are making sure we receive reports from the police as to the safety of the event," Fisher said.
"A lot of them have communicated that they do have confidence with the Edmonton Police Service and the RCMP, and if they're saying that it's safe for us to proceed, then we shouldn't be afraid to proceed."