PROVO Publishers agonized over lost sales when TV talk show icon Oprah Winfrey stopped endorsing a book each month in 2002.
Now a new Brigham Young University study could open old wounds.
Even casual observers knew regular sel- ections for Oprah's Book Club zoomed up best-seller lists but they also remained there longer than other titles, according to research done by BYU economist Richard Butler and two of his students.
The combined impact the "Oprah Effect" was worth hundreds of millions of dollars.
"Oprah's recommendations had a bigger impact on the sales of books than anything we have previously seen in literature, or seen since," Butler said.
Before Oprah's selection, only 11 of the 45 non-children's books she endorsed on her TV show between 1996 and 2002 had made USA Today's top 150 best-seller list. None had risen higher than 25th.
The first 11 books she picked had been unranked before gaining her stamp of approval, but each rocketed immediately into the top four.
But Oprah's real influence, Butler and his students found, was in her endorsements' staying power. They compared the duration of each of her picks on the list with how long other books spent in the top 150.
Among those most affected were "Poisonwood Bible" by Barbara Kingsolver, which was on the list for 137 weeks, and "Where the Heart Is" by Billie Letts that lasted 98 weeks on the list.
"It's not just an overall average," Butler said. "We're comparing the short-term, median-term and long-term books with Oprah's short-term, median-term and long-term books, and those are really distinct. Her average and below-average picks stayed on the list much longer than the average and below-average best-seller books."
And when Oprah-endorsed titles showed up on paperback best-seller lists a year after being on the hardcover lists, they remained in the top 25 for an average of 6.5 weeks.
The researchers conducted statistical tests to verify that their results were strictly correlated with the Oprah effect and not the product of chance or other variables. The paper was accepted by the academic journal Publishing Research Quarterly.
Butler believes the Oprah effect was fueled by thousands of book clubs around the country, according to an unpublished study his team conducted. One finding of the research, which has been submitted for review to the Journal of Cultural Economics, is that Oprah's selections fared worse during the summer months and in December, when book clubs generally don't meet.
"As a social scientist I was interested in why," Butler said. "I think it is because she played a decision role. This was a way to minimize tensions between book-reading clubs. Members knew her books would be available, topical and easy to discuss."
More than 8.6 million viewers watched Oprah's daytime talk show during the first week of December and her magazine has a circulation of nearly 3 million.
The Oprah effect was repeated with a new twist this fall with "Oprah's Favorite Things," which has increased the sales of products she gives away on her show. The popularity of the new idea has boosted the show's ratings by 15 percent this year to the highest numbers she's had since 1996, according to Nielsen Media Research.
Oprah resurrected her book club in 2003 but announced she would only endorse classics, which predictably have sold very well, also. That is a new area of study for Butler, BYU senior economics major Sebastian Nilsson and Benjamin Cowan, now a University of Wisconsin graduate student.
"Her book club still moves books," Butler said. "She still has power, even though the authors are dead, to move books for them."
Since he's not dead yet and just published a book of his own, "Death Hollow," Butler wouldn't mind if Oprah went back to publicizing lesser-known contemporary authors."I would love to have Oprah pick one of my books," he said.