The diary has been praised for its literary merits. Commenting on Anne Frank's writing style, the dramatist Meyer Levin commended Frank for "sustaining the tension of a well-constructed novel", and was so impressed by the quality of her work that he collaborated with Otto Frank on a dramatization of the diary shortly after its publication. Levin became obsessed with Anne Frank, which he wrote about in his autobiography "The Obsession". The poet John Berryman called the book a unique depiction, not merely of adolescence but of the "conversion of a child into a person as it is happening in a precise, confident, economical style stunning in its honesty".