Normal and abnormal sleep

  • Difficulty getting to or staying asleep; non-restorative; affecting functioning (> 3 days per week, > 1/12 ) 
  • Sleep onset latency (SOL) (abnormal > 30mins) 
  • Wake after sleep onset (WASO) (abnormal > 30mins) 
  • Total sleep time (TST) (abnormal <6 hours or >9 hours)
  • Sleep efficiency (SE) (abnormal <85%)



Sleep diaries can be used to rapidly assess the extent and nature of patients’ insomnia.
DSM-V characterises the following symptoms in adults:

  • Difficulty initiating sleep; in children this may be manifested as difficulty initiating sleep without caregiver intervention 
  • Difficulty maintaining sleep characterized by frequent awakenings or problems returning to sleep after awakenings (in children this may be manifested as difficulty returning to sleep without caregiver intervention) 
  • Early morning awakening with inability to return to sleep 
  • Non restorative sleep

Sleep diaries recorded over a period of 7 to 14 days by the patient can be used to measure the following sleep quality indicators (abnormal values in brackets):

  • Difficulty getting to or staying asleep; non-restorative; affecting functioning (> 3 days per week, > 1/12 ) 
  • Sleep onset latency (SOL) (> 30mins)  
  • Wake after sleep onset (WASO) (> 30mins) 
  • Total sleep time (TST) (<6; >9 hours)
  • Sleep efficiency (SE) (<85%)



Sleep onset latency (SOL) : Time from the decision to sleep to the onset of sleep.
Wake time after sleep onset (WASO) : Time spent awake from sleep onset to final awakening.
Total sleep period (TSP): Time from sleep onset to final awakening from the main sleep period of the day.
Total sleep time (TST) : Total sleep period minus the time spent awake during the sleep period
Sleep efficiency (SE) : Ratio of total sleep time to nocturnal time in bed