A new book focusing on HIV disclosure issues suggests that many HIV-positive people fail to tell their sexual partners that they are infected with HIV, with about one-third of the HIV-positive gay men surveyed for the book admitting to lying about their serostatus, The New York Times reports. However, the book's writers believe the actual number of HIV-positive gay men who lie about their serostatus to be significantly higher. "I was horrified by some of the things people told me," psychiatrist Robert Klitzman, co-author of Mortal Secrets: Truth and Lies in the Age of AIDS, told the Times. "At the end of each interview we spoke to the subjects about safer sex and the importance of disclosure. But it led us to think about the importance of a code of sexual ethics." Klitzman and Ronald Bayer, an ethicist, used oral history interviews of the sexual practices of 49 men and 28 women in New York City as the foundation for the book. Although the interviews were conducted from 1993 to 1996, before the advent of highly active antiretroviral therapy, the authors and other health experts believe little has changed since then with regard to disclosure levels. Sharon Byrd of the Michigan Department of Community Health told the Times that her current research showed as few as 20% of HIV-positive Detroit residents tell their sex partners of their infection. Many health officials attribute a failure to disclose HIV status, either intentionally or unintentionally, as a contributing factor to the continued spread of HIV in the United States. Bayer said disclosure issues are affected by many factors, including AIDS stigma and a fear of discrimination, even by friends and family members.