Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Book about testosterone replacement therapy

The book is in the main about the author's views on testosterone replacement therapy, but just about mentions vasectomy in passing. It's fair to say that the vasectomy information reviewed is highly selective, in the main 15 plus years old, and contradicted by much newer and much better research. What information on vasectomy there is just so happens to fit in with the author's view on testosterone replacement therapy, which he just happens to practice. Coincidence???