If you buy stuff on Amazon...if you haven't, you probably will, sometime, you probably check out buyer reviews...with some it's easy to spot a fake review. Others, not so much.
So, it isn't news (I hope) that sellers like good reviews and there's a group of folks who earn money by 'reviewing' products for pay. Many sites don't do this, allowing only buyers to leave reviews, but there are 'work arounds' such as sending the 'reviewer' samples.
http://fakespot.com/ is one site which analyzes and reports fake reviews on Amazon and Yelp business reviews, and gives adjusted ratings on that basis. It won't do that for regional Amazon sites.
"Fakespot grades the product reviews of the item, displays an adjusted rating, Amazon's rating, and provides you with information on the authenticity of the ratings. It may for instance tell you that "there are indications of inauthentic/low quality reviews". The analysis digs deeper than that, as it provides you with information on the reviews.
It may give you words used to describe the product, the percentage of low quality reviews, and even information on inauthentic reviews, and why they were classified as that (automation, correlation with other fake reviewer profile data and languages). Fakespot supports only Amazon.com, but no regional Amazon sites." - gHacks
https://reviewmeta.com/ checks reviews as well, using algorithms to adjust the overall rating. It works for regional Amazon sites, though, as well.
"The service will adjust the rating and reviews based on its algorithm, display a report card that highlights checks the product reviews passed, failed or looked suspicious, and lists most and least trusted reviews.
What follows is a detailed analysis of all reviews. ReviewMeta lists the ratio of one-time reviewers to reviewers who have left multiple reviews on Amazon, the percentage of reviewers without any verified purchases, phrase repetition, and a lot more." - ibid
So, besides checking Consumer Reviews and other reliable sites, you have additional options now by just pasting the product link from Amazon into the box on Fakespot or Reviewmeta.
I'd recommend bookmarking one or both sites.