Or sometimes when I get varying information, I'll do what some statisticians do: When faced with a range of different results, I'll throw out the highest and lowest figures from that range, then take an average of the rest.
Maybe they're doing their own research and publishing those findings/recommendations, or just accessing different studies done by someone else?
Just like another member commented to me yesterday, I think it's all a crap shoot. There are so very many variables that it's hard to pin down the...