Doody’s Star Ratings®

Perhaps the most recognizable element in a Doody’s review, Doody’s Star Ratings® represent the reviewer’s quantitative analysis of the product being reviewed. In addition to preparing a qualitative assessment of the book or software title, reviewers are asked to fill out a questionnaire, rating the product on 18 different elements on a 1-to-5 or 1-to-10 scale.

Their rankings yield a numerical score, with 100 being a perfect score. Numerical scores are then plotted on a bell curve, and roughly 5% of all titles receive a score of 5 stars (the best) or 1 star (the poorest); another 25% of the titles are awarded 2 stars or 4 stars; and the remaining 40% of the titles earn 3 stars.
 
Five stars are awarded to books that score between 97 and 100 points. The ratings for four star books range between 90 and 96. Books ranked between 69 and 89 earn three stars. Two star books score in the range of 47 to 68. And one-star books have scored 46 points or less.