PSQI score interpretation: total and seven components

A PSQI score, or global Pittsburgh Sleep Quality Index score, runs from 0 to 21 and sums up how you’ve slept over the past month. A score of 5 or less fits the pattern of good sleep, and 6 or more fits the pattern of poor sleep, with higher numbers meaning more parts of your sleep are struggling. The total is built from seven smaller scores, and those seven parts usually tell you more than the number itself. It’s a sleep questionnaire, not a diagnosis of any sleep disorder.

What is the Pittsburgh Sleep Quality Index?

The Pittsburgh Sleep Quality Index (PSQI) is a questionnaire about your usual sleep over the past month. Daniel Buysse and colleagues at the University of Pittsburgh published it in 1989 in the journal Psychiatry Research, and it has become one of the most widely used sleep questionnaires in research and clinics around the world.

It was built to answer a simple question: is this person sleeping well or badly overall? Instead of asking that directly, it collects the details that make up a night. When you usually go to bed and get up, how long it takes you to drop off, how many hours you actually sleep, what wakes you, whether you take anything to help you sleep, and how you cope during the day.

The paper version also has a few questions for a bed partner or room-mate, about things like loud snoring or long pauses in breathing. Those answers aren’t added to the score, so Sprout leaves them out. The sleep quality test on Sprout asks the other 18 questions and takes about five minutes. Taking the test is free; results need Sprout Plus (7 days free).

What are the seven PSQI components?

The PSQI turns your answers into seven component scores, each from 0 (no difficulty) to 3 (a lot of difficulty). Sprout shows them under More detail on your result. The table shows what each component measures and how it’s scored.

Some parts are a single answer, like your own rating of your sleep. Others combine answers. Time to fall asleep adds a score for your usual minutes (15 or fewer is 0, 16 to 30 is 1, 31 to 60 is 2, more than 60 is 3) to how often you couldn’t get to sleep within 30 minutes, then turns that sum back into a 0 to 3 score. Things that wake you adds up how often each of the nine disturbances happened and turns the total into 0 to 3 in the same way.

Time in bed spent asleep is the one people find least intuitive. It compares the hours you actually sleep with the hours between going to bed and getting up. Someone who sleeps seven hours in an eight-hour stretch is asleep about 88 percent of the time; someone who sleeps six hours in the same stretch is at 75 percent, and the part scores higher.

How is the global PSQI score worked out?

The global PSQI score is the seven component scores added together, so it runs from 0 to 21. There’s no weighting: a 2 for daytime tiredness counts exactly as much as a 2 for hours of sleep.

This worked example uses a fictional person, not real data:

• Rating: they call their sleep fairly bad, which scores 2.
• Falling asleep: it usually takes 25 minutes (1), and once or twice a week it takes more than 30 (2). The sum of 3 gives a part score of 2.
• Hours: they sleep about 6.5 hours, which scores 1.
• Time in bed asleep: they’re in bed from 11pm to 7am, eight hours, and asleep for 6.5 of them. That’s 81 percent, which scores 1.
• Things that wake them: waking in the night three or more times a week, the toilet once or twice a week, feeling too hot less than once a week. The small total gives a part score of 1.
• Medicine: none, which scores 0.
• Daytime: rarely nodding off, but some trouble keeping up enthusiasm. That gives a part score of 2.

Their global score is 2 + 2 + 1 + 1 + 1 + 0 + 2 = 9. The total lands in the poor sleep range even though the person gets 6.5 hours, more than many people get. The PSQI combines several difficulties: taking time to fall asleep, waking during the night and sleeping fewer hours.

What is a good PSQI score?

A good PSQI score is 5 or less. Sprout calls that range good sleep, and it means your answers fit the pattern of good sleep over the past month: mostly enough of it, falling asleep without much trouble and feeling okay during the day.

The cut-off between 5 and 6 comes from the original study. Buysse and colleagues compared people without sleep complaints with patients who had sleep problems, and a global score above 5 sorted them well: it correctly picked out about 90 percent of the patients and about 87 percent of the people sleeping well. That is why 5 remains the cut-off.

A good score doesn’t need to be zero. Even when sleep is going well, one or two parts often pick up a point for something small, such as the odd night of waking up too hot or needing the toilet. What matters is whether the total stays at 5 or below.

What does a score of 6 or more mean?

A score of 6 or more means your answers fit the pattern of poor sleep over the past month. Sprout uses one band name, poor sleep, for the whole range from 6 to 21, but the number within it still matters, so the result describes the lower and upper parts differently.

A score of 6 to 10

Parts of your sleep haven’t been going so well. It might be taking a while to fall asleep, you might be waking in the night, or you might not be getting quite enough sleep. This is very common, and it’s often the range people land in during a stressful stretch, a new baby, a change of job or a run of late nights. Regular sleep and wake times, some daylight in the morning and a wind-down before bed can all help. If it carries on or gets in the way of your days, mention it to your doctor.

A score of 11 to 21

Sleep seems to have been a real struggle in several ways, and it’s likely affecting how you feel and cope during the day. Poor sleep can wear down mood, energy and concentration. Many sleep problems can be helped, so it’s worth talking to a doctor about what might be behind yours. Take extra care with driving when you’re very tired.

Which PSQI component is raising your score?

Look at which of the seven parts score 2 or 3, because they show what kind of sleep problem you have, and different problems need different help.

• Time awake in bed: being slow to fall asleep or spending lots of time awake in bed often goes with insomnia, especially if worry or a busy mind keeps you up. The insomnia check looks at it more closely, and the ISI score ranges explain its results.
• Short nights: if you fall asleep quickly, you may simply not be giving yourself enough time in bed. A later wake-up time or an earlier bedtime can be the whole answer.
• Many things waking you: look at which ones. Heat, noise and a partner’s movements can sometimes be changed. Pain, needing the toilet often at night, or trouble breathing are worth raising with a doctor.
• High daytime tiredness: if you struggle to stay awake in quiet moments, the ESS score ranges are the next thing to look at. If you feel flat rather than sleepy, mood or stress may be part of it.
• Regular sleep medicine: this part scores higher simply because you take something, even if it works. That’s not a judgement; it’s worth reviewing with a doctor now and then.

Two people with the same global score can have completely different nights. A 9 made of short sleep and daytime tiredness is a different problem from a 9 made of slow sleep onset and lots of time lying awake.

What can’t the PSQI tell you?

The PSQI can’t diagnose a sleep disorder. It shows how well you’ve been sleeping overall and which parts are struggling, but it can’t say whether you have insomnia, sleep apnoea or anything else. Only a doctor or sleep specialist can assess that, often with more questions, a sleep diary or a sleep study.

A few other limits are worth knowing:

• Monthly recall. It relies on your memory of a month. Most people estimate their sleep roughly, and people with insomnia often underestimate how much they sleep. That doesn’t make the score wrong, but the hours are a best guess.
• It doesn’t explain why. A high score could come from stress, a noisy street, shift work, pain, low mood or a physical cause. The number points to where to look, not to the answer.
• It misses what happens while you’re asleep. Loud snoring or pauses in breathing are usually noticed by someone else. If a partner has mentioned them, tell your doctor, whatever your score.
• It treats every part equally. A score of 3 for sleep medicine adds as much as a score of 3 for hours of sleep, even if the medicine is helping.

How does the PSQI compare with other sleep questionnaires?

Choose the PSQI for an overall picture of sleep, the Insomnia Severity Index when lying awake is the main problem, or the Epworth Sleepiness Scale for daytime dozing. The PSQI is the broadest of the common sleep questionnaires; the others focus on a specific difficulty.

If you aren’t sure whether your tiredness is about sleep at all, the post on constant tiredness sorts through sleep, mood, stress and physical causes.

What should you do with a poor sleep score?

Start with the component that scored highest and choose a next step that addresses it. Keep a note of your score and the date so you can compare next month.

• Keep your wake-up time steady. Getting up at the same time every day, weekends included, is one of the simplest ways to steady your body clock.
• Get some daylight early. Time outside in the morning helps your body know when it’s day.
• Give yourself a wind-down. A calm half hour before bed, away from work and bright screens, makes it easier to drop off. Slow breathing helps some people; the post on a bedtime breathing method explains one, and the guided breathing practice walks you through it.
• When tips haven’t worked. If you’ve already tried the usual advice and still lie awake, that’s common and has a reason. Help beyond sleep tips explains the next options.
• Talk to a doctor. Do this if your score is 11 or more, if poor sleep has lasted more than a few weeks, if you struggle to stay awake during the day, or if someone has noticed loud snoring or pauses in your breathing.

Bringing your result to a doctor

The seven parts are useful to show a doctor, because they turn “I sleep badly” into something specific: “It takes me over an hour to fall asleep most nights, and I’m asleep for about two thirds of the time I’m in bed.” A doctor can check what’s behind poor sleep, look at medicines or health problems that might play a part, and talk through approaches that help, many of them without sleeping pills.

How often should you retake the PSQI?

About once a month, because the questions ask about the past month. Taking it more often mostly measures the same nights twice.

The trend is more useful than any single result. If you change something, such as a new wake-up time, cutting caffeine after lunch, or starting a course of therapy for insomnia, retaking it a month later shows whether the change is reaching your sleep. Watch the parts as well as the total: time to fall asleep might improve before hours of sleep do.

If you’d like to see where your sleep stands now, the five-minute sleep check gives you the global score and all seven parts, so you can see which one to work on first.