According to research firm YouGov, the main reasons given for accessing reviews are to ensure the product or service is of good quality (79%), that it works (61%) and to make sure they don't get ripped off (53%), Marketing Charts reported.
Written content is important for 90% of US consumers, but interestingly the study found they attach similar levels of importance to a reviewer's star ratings.
Overall, 87% who read any online reviews find the star ratings to be important to their purchase decision and just over a third (34%) think they're "very important".
The most read reviews are for electronics (53%), household appliances (43%), car purchases (40%) and hotels or short-term room rentals (36%).
But, while the great majority of Americans turn to reviews to aid their research, they remain sceptical about some of the claims made in them.
Most do find reviews trustworthy, but only 13% believe they are "very trustworthy" and a full 90% believe that some people review products and services without trying them.
A similar proportion (91%) believe companies write their own positive reviews and 89% think businesses write negative reviews about their competitors.
Among those who do post online consumer reviews, 62% are motivated by wanting to help others while 35% feel it is polite to leave feedback.
More than a quarter (27%) want to share a positive experience, 25% want to help good vendors to gain business while only 12% are seeking to expose bad ones.
Finally, it appears reviewers from the Midwest are more reliable than those in other parts of the country because they admit to significantly fewer fraudulent reviews.
Data sourced from YouGov, Marketing Charts; additional content by Warc staff