Close Popup

Download SleepRate Now!

Download the App Get SleepRate
back

Subjective Measures of Sleepiness

Two standard tests are used frequently to assess degrees of sleepiness.

Stanford Sleepiness Scale (SSS)

In 1973 sleep scientists at Stanford University developed a subjective measure of alertness called the Stanford Sleepiness Scale. Individuals rate themselves according to one of several statements that most closely describes their level of alertness or sleepiness.

To collect a spectrum of sleepiness indicators across a day, the SSS is administered at two-hour intervals, usually during the waking part of the day. To correlate objective measures and subjective feelings of sleepiness, the SSS may also be administered immediately before and after naps during a multiple sleep latency test.

The SSS uses the following numeric scale:

1:  Feeling active, vital, alert, and wide awake.
2:  Functioning at a high level but not at peak performance. Able to concentrate.
3:  Relaxed and awake, but not fully alert. Still responsive.
4:  Feeling a little foggy and let down.
5:  Foggy and beginning to lose track of things. Difficult to stay awake.
6:  Sleepy and prefer to lie down. Woozy.
7:  Almost in reverie and cannot stay awake. Sleep onset is imminent.

Epworth Sleepiness Scale (ESS)

The ESS is a short questionnaire that measures daytime sleepiness and is useful for the detection of sleep disorders. It was introduced in 1991 at the Epworth Hospital in Melbourne, Australia. The ESS asks for subjects to rate (on a scale of 0 to 3) his/her propensity to fall asleep in eight different situations.

The questionnaire is below.

The following questions refer to sleepiness or the tendency to doze off when relaxed.

How likely are you to doze off or fall asleep in the following situations, in contrast to just feeling tired? This refers to your usual way of life in recent times. Even if you haven’t done some of these things recently, try to work out how they would have affected you.

Use the following scale to choose the most appropriate number for each situation:

0 = would never doze
1 = slight chance of dozing
2 = moderate chance of dozing
3 = high chance of dozing

Situation Chance of Dozing
1. Sitting and reading…………………
2. Watching TV…………………
3. Sitting, inactive in a public place (eg. theatre or a meeting)…………………
4. As a passenger in a car for an hour without a break…………………
5. Lying down to rest in the afternoon when circumstances permit…………………
6. Sitting and talking to someone…………………
7. Sitting quietly after a lunch without alcohol…………………
8. In a car, while stopped for a few minutes in traffic…………………
________________________________________________________________________________________________
Add up all answers    :…………………

 

 

After completion of the questionnaire the scores are added together and the number is assessed on a range to determine the possibility of a sleep disorder.

How Will SleepRate Help You?

Use SleepRate for a few days to identify sleep-wake patterns and to measure sleep duration, efficiency and structure. If those measurements suggest a condition that warrants further investigation, you’ll be prompted to consult a physician for an in-depth sleep evaluation.

Find out more about SleepRate. Or, if you’re ready to purchase a SleepRate package, start here.

SleepRate Home Page

Tell Us What Do You Think...

shares