F51 NONORGANIC SLEEP DISORDERS
Comments: a more comprehensive classification of sleep disorders is available (International Classification of Sleep Disorders1) but it should be noted that this is organized on a different basis than ICD-10. For some research purposes, where particularly homogenous groups of sleep disorders are required, a specification of 4 or more within a one-year period should be considered for categories F51.3, F51.4 and F51.5.
F51.0 Nonorganic insomnia
F51.1 Nonorganic hypersomnia
F51.2 Nonorganic disorder of the sleep-wake schedule
F51.3 Sleepwalking [somnambulism]
F51.4 Sleep terrors [night terrors]
F51.5 Nightmares