The average incidence of nightmare in adults is believed to be once or twice per year. There is about five percent of the population who experience very frequent nightmares (more than once a week). Between fifteen to twenty percent of college undergraduates report occasional nightmares: that is, one or more per month. Students majoring in Art tend to report the most nightmares, while students majoring in Physical Education report the least number of nightmares (Bearden, 1994).
Another factor that influences the prevalence of nightmare is age. The incidence of nightmare decreases as people get older, and is relatively low in healthy, elderly populations. Elderly subjects were only about one-fifth as likely as college students to report a problem with nightmares. Children between the ages of four and eight appear to have over a 50% chance to suffer from occasional nightmares. Children who wake from nightmares are typically alert, aroused, and often describe details of frightening images. These children typically have trouble going back to sleep and want parental interaction and reassurance. In addition to this these children continue to remember and talk about nightmare the following day. The incidence of "disturbing dream" was much lower in the age group of nine to fourteen year old children compared to the age group of seven to eight year old children. The prevalence due to gender and psychiatric patients are very unclear, simply due to the lack of reporting by men compared to females and the lack of patients cooperation.
According to Krakow et. al. (2001) nightmare prevalence in children and adolescents is fairly high as well. Rates ranged from a peak in early childhood of 42.2% at age of 2.5 years followed by a progressive descent toward adolescence with a final prevalence of 7.3% at age of 16 years. For adult chronic nightmare sufferers, 42% reported an onset before the age of 15 years and slightly more than one-half of adult chronic nightmare sufferers developed their problem before the age of 20 years. Thus, a substantial number of adolescents appear to suffer from chronic nightmares and it persists to adulthood. There are several different Types of Nightmares.