I also received a call from this number for the Canadian Liver Foundation.  It is actually not a scam, which I confirmed by calling the published number for the Canadian Liver Foundation and simply asking them if they had any active outbound campaigns.  I was told yes they do and they even confirmed the number is a legitimate source for this.  I simply responded to the callers that I do not give payment information for anything where I have not been the initiator of the call and that I would go to their website to donate.  They also offered to send me the pledge form as an alternative.  So, not a scam but you don't have to donate.  Just ask some questions!