Other diagnostic studies for insomnia include polysomnography, which demonstrates findings of underlying sleep disorders such as obstructive sleep apnea, and periodic limb movement disorder; multiple sleep latency test, which demonstrates mean sleep latency ≤8 min with at least 2 sleep-onset REM periods in patients with narcolepsy; and actigraphy, which demonstrates increased sleep onset latency, increased wake after sleep onset, increased total sleep time, increased number of wakings during night, and decreased sleep efficiency.

Other diagnostic studies for insomnia include:

• Polysomnography, which demonstrates:^{_SpringerLink-1|[1][2]}
  • In patients with obstructive sleep apnea
    • Five or more apneas, hypopneas or arousal due to respiratory effort per hour of sleep and a respiratory effort during these events
  • In patients with periodic limb movement disorder
    • Stereotyped limb movements during sleep
      • Takes 0.5 – 5 seconds
      • Amplitude ≥25% of toe dorsiflexion while the calibration occurs
      • Sequence of at least 4 movements
      • Duration of (5-90)sec between intervals
• Multiple sleep latency test, which demonstrates:^[3]
  • In patients with narcolepsy
    • Mean sleep latency ≤8 min with at least 2 sleep-onset REM periods
• Actigraphy, which demonstrates:^[4]
  • In patients with insomnia
    • Increased sleep onset latency
    • Increased wake after sleep onset
    • Increased total sleep time
    • Increased number of wakings during night
    • Decreased sleep efficiency