Other European names in the early history of epidemiology of sleeping habits, insomnia, and sleep apnea include Heikki Palomäki (stroke) , John Stradling (neck circumference, risk factors, hypertension) , Neil Douglas (RCTs, cognition, etc.), Erkki Kronholm (sleep length, insomnia), and Claudio Bassetti (stroke) among many others. Talking about history of cardiovascular studies on sleep apnea in Europe, one cannot forget Marburg (Germany). Jörg Hermann Peter was a pioneer in that field, and he organized several important meetings on the topic before he passed away in January 2010. Some of the studies that originated in Marburg are now being continued in Gothenburg, Sweden, by Ludger Grote and Jan Hedner. One of the pioneers in the area of narcolepsy and hypersomnias had been Prof. Bedrich Roth from Prague (Czech Republic). He was born in 1919 and he passed away in 1989. He published his first monograph on narcolepsy in 1957. His blue book on hypersomnias with epidemiological data remains a classic. Sonia Nevsimalova and Karel Sonka are continuing his pioneering work.

Several US groups, in addition to Bixler and Young, have conducted excellent epidemiological studies. One important researcher is Maurice Ohayon who is a psychiatrist. He became more and more interested in sleep epidemiology after moving from France to Canada. The first epidemiological study using the so-called Sleep-EVAL system was published in 1996 [51]. Since that time, he has published several cross-sectional studies on the occurrence of different sleep disorders.

There are many other Asian, European, and US colleagues who have conducted epidemiological studies in different areas. The list of researchers would be too long, and I have listed only some people who have been important in the history of sleep medicine during its development mainly in the 1980s to the 1990s. I apologize to all of those whose names are missing. Happily, more and more people are interested in sleep epidemiology. With the advent of efficient computers and good registries, studies changed from simple descriptive ones to well-planned case–control, prospective, and multivariate analytic studies of different associations and risk factors.