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Attempting to Measure Sleep Deficiency and Sleepiness

The information on this website is not intended to replace a one-on-one relationship with a qualified health care professional and is not intended as medical advice. Read our full medical disclaimer.

Sleep deficiency is unlike other conditions of the human body. It is not easy to measure. There are physical characteristics associated with sleep deficiency. These are signs indicating that a person is sleep-deprived. A common sign of sleep-deficiency is eyebags. A person is also sleeping deprived or even just sleepy when his eyelids flutter too much. However, these signs are not measurable. Sleep deficiency is also different from one person to another. Two persons who had equal length of sleep will feel sleepy during different times.

Sleep deficiency

Sleep deficiency is just like, but not exactly the same, as sleep deprivation. Sleep deficiency is a broader term. It covers the results of lack of sleep. Sleep deficiency is a common health problem in the United States. Around 7 to 19 percent of people don’t get enough sleep each day. A study also estimates that 40% of adults have unintentionally fallen asleep at least once a month. What is more alarming is the fact that up to 70 million Americans suffer from some type of chronic sleep disorder.

However, sleep deficiency often causes other health-related issues. It can cause diabetes, kidney problems, obesity, high blood pressure, or depression. This can also result in difficulties with learning, focusing, and memory. It can also affect a person’s mood and emotions.


Sleepiness is a feeling that a person feels when the sleeping time approaches. There are physical signs accompanying it. A person begins to yawn and his eyelids begin to flutter. The thoughts of a sleepy person also start wandering to dreamland. This is what a person with normal sleep patterns feel when sleepiness comes.

How are they measured?

It is difficult to measure a person’s level of sleep deficiency and sleepiness. These two depend on a lot of different factors. Even if there are a lot of ways to determine a person’s state of sleep, it can be hard to estimate it. This is because a person’s state of sleepiness might change any minute.

Reaction time

A person’s reaction time is a way to measure sleepiness and alertness. This can be a bit inaccurate. A person’s reaction time may depend on a lot of factors.  A lot of things can affect a person’s reaction time. Things like brain injuries or medications can affect a person’s reaction time. The unreliability of this method is due to the fact that it cannot be adjusted. It is also not objective enough. This method of measurement is not adjustable to accommodate external factors.

When used in diagnosing sleep disorders, doctors can use several tests in combination. One of these is the psychomotor vigilance test. It is a brief test. Often, it takes less than 3 minutes to complete. It comes in the form of a simple interactive video. During the test, a patient’s quick responses get measured. This provides doctors valuable information about a person’s reaction time. It also gives medical professional information about a person’s overall alertness.  


Biomarkers are a means of measuring a disorder’s effects on a body. It relies on the changes that a disorder does to a body. An example is the changes in the blood oxygen level of a body. Or a person’s blood pressure. Unfortunately, there are currently no reliable biomarkers for sleepiness and sleep deficiency.

A scale

In 1990s, Dr, Murray John created an Epworth Sleepiness Scale for children and adolescents. It is a short questionnaire. This questionnaire requires scaled answers. There are 8 questions in this scale. Each question is answerable with a 4-point scale for answers.


Multiple Sleep Latency Test is a way of collecting data about a patient’s sleep habits. This is useful especially in measuring daytime sleepiness. It can help determine how quickly a person may fall asleep. The MSLT requires a person to take 5 scheduled naps. These naps have 20-minute breaks in between. It makes use of sensors that determine if a person is sleeping. There is also a sensor to check in which sleep phase a person is.

Maintenance of Wakefulness Test

This is a test that a doctor can use to measure a patient’s alertness. It can help determine if a person can stay awake for a scheduled period of time. This is different from other sleep studies. Most sleep studies require a person to sleep. With the MWT, a person needs to stay awake. An example is requiring a person to sit still without doing anything that can stimulate their wakefulness. During this test, the patient gets monitored for eye and chin movements. The patient’s heart and brain activity also get monitored. Other activities often used in this test include watching a TV or reading a book. It also includes daily activities like eating or walking. If a patient is free of sleep disorders, they should not encounter any problems staying awake during this test.

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The information on this website is not intended to replace a one-on-one relationship with a qualified health care professional and is not intended as medical advice. Read our full medical disclaimer.

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