There are many different questionnaires, but the Epworth Sleepiness Scale and the Stanford Sleepiness Scale are two of the more popular.
The Epworth sleepiness scale
This questionnaire suggests eight scenarios which may happen during a typical day, such as watching television or sitting inactive in a public place.
You are asked to rate on a scale from 0 to 3 your chances of dozing off in each situation, where 0 is no chance and 3 is high chance.
All your individual scores are added up to give a maximum of 24 points. The higher the score, the sleepier you are considered to be during your daily activities.
Stanford sleepiness scale
This questionnaire can be used to find out how alert or sleepy you are during a typical day. It is completed at several different times in one day to track how your sleepiness changes as the day progresses.
It can be used to map points where you are feeling alert and other times when you are feeling sleepy.
It has a seven point scale, from 1 which is ‘active, vital, alert or wide awake’ to 7 which is ‘sleep onset soon; having dreamlike thoughts’. There is also an X for ‘asleep’.
If the score rises above 3 at points in the day when you should be alert, or you fall asleep, it may indicate a sleep disorder or lack of adequate sleep.
Usefulness of questionnaires
Questionnaires are a good way of showing how you currently feel. They can assess how your sleepiness is affecting your ability to complete daily activities. They indicate how much benefit you may gain from treatment for sleep apnoea, such as positive airway pressure therapy.
You may also be asked to complete the same questionnaire once you have started treatment. It is a useful way to show improvements in your daytime sleepiness.
Questionnaires can also highlight the need for further investigation or alterations to your treatment if you remain sleepy. Although they may seem like extra paperwork, they provide valuable information that can help guide your sleep specialist, so it is important to fill them out honestly and accurately.
Questionnaires are subjective
There are many sleepiness questionnaires but they all have one drawback in common – they are subjective. This means they depend on your feelings and perspectives at one instant in time, so the results of each questionnaire may vary depending on your mood.
To overcome this limitation, many questionnaires ask you to consider your sleepiness over a period of time rather than on any one day.
