What is the prevalence of insomnia in a particular age group, in men and women, or in Caucasians and African Americans? What is the average total sleep time among normal sleepers among these groups? How does the sleep of Caucasians and African Americans differ? These are just some of the questions addressed in The Epidemiology of Sleep. This new book presents the most detailed and comprehensive archive of normal and abnormal sleep patterns. Based on a landmark study supported by the National Institute on Aging, 772 subjects from a host of populations including men, women, and various age and ethnic groups, prepared detailed sleep diaries for a two-week period. The use of these sleep diaries yielded a plethora of data on such characteristics as normal sleep patterns, various forms of insomnia, fatigue, depression, anxiety, and daytime sleepiness differentiated by age, sex, and ethnicity. The results generated by these data, charted in the book's numerous tables and graphs, provide a critical methodological advance in the sleep literature. The Epidemiology of Sleep opens with an overview of the rationale and unique characteristics of the study. This is followed by a comprehensive review of the existing epidemiological literature on sleep. Chapter three presents a detailed description of the methods used in the survey followed by meticulous information on the epidemiology of normal and insomnia sleep, that is unparalleled in the literature. Chapter six provides an archive of sleep patterns among African Americans. The book concludes with a discussion and interpretation of the most interesting findings.