Assessments of Sleepiness

These two quick questionnaires are used at the Stanford Center for Excellence in the Diagnosis and Treatment of Sleep Disorders, to determine whether a person is getting enough sleep.  Click on the following links, complete the scales, and then follow the instructions to interpret your results.

Epworth Sleepiness Scale

(An Assessment of How Sleepy You Are)


Stanford Sleepiness Scale

(A Quick Asssessment of "Sleep Debt")


Iowa Sleep Experiences Survey

The purpose of this survey to examine the prevalence of various sleep- and dream-related  phenomena in the general population. Please answer the following questions honestly and accurately. Read each statement carefully, then indicate how frequently you have experienced this phenomenon.

Use the following scale to record your responses:

0 = never

1 = rarely (that is, less than once a year)

2 = infrequently (once or twice a year)

3 = occasionally (several times a year)

4 = frequently (once or twice a month)

5 = very frequently (several times a month)

6 = regularly (several times a week)


  1. Upon awakening during the night, I am unsure whether I actually experienced something or only dreamed about it.
  2. Lying in bed, I sense the presence of someone who actually isn't there.
  3. As I lie in bed, I realize that I am unable to move
  4. My legs twitch or tremble as I lie in bed.
  5. My body suddenly jerks violently as I begin to fall asleep.
  6. I experience intense, dreamlike images as I begin to fall asleep.
  7. I experience intense, dreamlike images as I begin to awaken.
  8. I am aware that I am dreaming, even as I dream.
  9. I am able to control or direct the content of my dreams.
  10. I am able to wake myself out of dreams that I find unpleasant or disturbing.
  11. I have spells of sudden, overpowering sleepiness during the day.
  12. While awake, I experience a sudden weakness in my body muscles during states of strong emotion such as anger or excitement.
  13. I walk in my sleep.
  14. I talk in my sleep.


  15. I remember my dreams.
  16. I have a dream that is so vivid it influences how I feel the following day
  17. I have nightmares.
  18. I have dreamed that I was falling.
  19 I have dreamed that I was flying.
  20. I have dreamed that I woke up (that is, waking up was part of the dream experience).
  21. 21. I have recurring dreams.
  22. I have dreamed about something that later actually happened.
  23. I have died in a dream.
  24. A dream helped me to solve a current problem or concern.


Scoring Key

The General Sleep Experiences Scale is the sum of the following items:

#1, #2, #6, #7, #12, #15, #16, #17, #18, #19, #20, #21, #22, #23, #24

Lucid Dreaming is the sum of the following items:

#8, #9, #10

Unfortunately, no population norms are available for the ISES.  However, you may use the items as a vehicle for reflecting on your own experiences during sleep.


For more information about the ISES, see:

Watson, D. (2001). Dissociations of the night: Individual differences in sleep-related experiences and their relation to dissociation and schizotypy. Journal of Abnormal Psychology, 110, 526-535.

Watson, D. (2003). To dream, perchance to remember: Individual differences in dream recall. Personality and Individual Differences, 34, 1271-1286.