NINDS CDE Notice of Copyright
Pittsburgh Sleep Quality Index (PSQI)
Pittsburgh Sleep Quality Index (PSQI)
Please visit this website for more information about the instrument:
Supplemental: Huntington's Disease (HD), Parkinson's Disease (PD), Myalgic encephalomyelitis/Chronic fatigue syndrome (ME/CFS), and Sport-Related Concussion (SRC) Subacute (after 72 hours to 3 months) and Persistent/Chronic (3 months and greater post concussion)
Exploratory: Spinal Cord Injury (SCI), Sport-Related Concussion Acute (time of injury until 72 hours), and SCI-Pediatric
|Short Description of Instrument||
Summary/Overview of Instrument: A self-rated questionnaire that primarily assesses nighttime sleep problems. It focuses on sleep experiences over the past month. It has 19 self-rated questions and 5 additional questions for a bed partner or roommate.
Construct measured: Sleep quality, sleep habits and sleep disturbances. Seven component scores: subjective sleep quality, sleep latency, sleep duration, habitual sleep efficiency, sleep disturbances, use of sleeping medication, and daytime dysfunction.
Generic vs. disease specific: Has been used in many different populations; it is not disease specific.
Intended use of instrument/purpose of tool: Can be used as a screening instrument for nighttime sleep disturbance or for clinical studies. It cannot be used to diagnose specific sleep disorders, but instead may help distinguish "good" versus "poor" sleepers.
Means of administration: Paper and Pencil
Location of administration: Clinic, Home
Intended respondent: Patient (with 5 supplemental questions for a bed partner or roommate).
# of items: 24 (19 self-rated items, and 5 supplemental items to be rated by a bed partner or roommate)
# of subscales and names of sub-scales: 7 – Subjective sleep quality, sleep latency, sleep duration, habitual sleep efficiency, sleep disturbances, use of sleeping medication, and daytime dysfunction.
Strengths: Extensive literature of its use in other populations. Includes several questions for bed partners (though these are not comprehensive and are not used in the scoring.)
Weaknesses: Primarily assesses nighttime sleep problems; wording might be confusing; does not directly address changes in circadian rhythms (sleep time shifting to the day and awake all night) that clinically is often observed in HD patients; the wording of certain questions is likely problematic for patients with HD and measures other constructs such as mood or motivation, e.g., "during the past month, how much of a problem has it been for you to keep up enough enthusiasm to get things done."
One study in an HD population found the education, daytime dysfunction SCOPA-S more internally consistent, and much easier to score and use than the PSQI (Aziz et al., 2010). The scoring algorithm is unusually complex.
SRC-specific: Used in several studies with population, sensitivity to SRC sleep problems is still unclear. No data in children. (Gosselin et al., 2009)
According to several studies assessed and repeated after a one year period the test scores demonstrate adequate sensitivity/specificity and positive/negative predictive value https://www.clinicalkey.com/#!/content/journal/1-s2.0-S1389945707004352
SCI-Pediatric-specific: Frequently used in adults, but no data in children. Most questions will be applicable to children, but more appropriate for parent report or adolescents to complete.
Translations available: Translated into 56 languages. Versions can be requested from University of Pittsburgh Sleep Medicine Institute website.
Scoring: Seven component scores are calculated, each scored from 0 to 3, the total score ranges from 0 to 21, with higher scores indicating more severe sleep problems in many areas. Scoring requires closely following a complex algorithm and is not a simple summation of answers. A cutoff of 5/6 for the total score is used in general populations to distinguish between "good" and "poor" sleepers. Scoring can be time consuming.
Standardization of scores to a reference population (z scores, T scores): The PSQI scores are not standardized to a particular population but this instrument has been used in many different populations.
If scores have been standardized to a reference population, indicate frame of reference for scoring (general population, HD subjects, other disease groups). (See above.) While the scores are not standardized to a particular reference population, the cutoff of 5/6 for "good" versus "poor" sleepers was developed from general population samples and thus it may not carry over as the best screening cutoff for specific populations such as HD subjects.
Reliability: Test-retest or intra-interview (within rater) reliability (as applicable): The Pearson correlation coefficient for test-retest reliability in a non-HD population was 0.87 and is stable over time (HÖgl et al., 2010). Inter-interview (between-rater) reliability (as applicable): not available in reviewed references Internal consistency: A Cronbach's alpha of 0.72 was found in a one HD study (Aziz et al., 2010); Cronbach's alphas of between 0.80 and 0.83 have been reported for the PSQI in different studies of non-HD populations.
Validity: Content validity: Not available in reviewed references Construct validity: In the original study, the instrument successfully discriminated between clinical populations of good sleepers (normal healthy controls) and patients from a sleep evaluation clinic. In a HD sample, the measure correlated highly with another sleep measure, the SCOPA-SLEEP.
Advantages: many of the questions are familiar to ME/CFS patients who do experience sleep issues and have many of the problems raised, including use of sleep meds.
Limitations: ME/CFS patients may not recall awakening during the night; many do not have a bed partner; some may have so many symptoms that they may not know what specifically awakened them at night.
Buysse DJ, Reynolds CF 3rd, Monk TH, Berman SR, Kupfer DJ. The Pittsburgh Sleep Quality Index: a new instrument for psychiatric practice and research. Psychiatry Res. 1989;28(2):193–213.
Aziz NA, Anguelova GV, Marinus J, Lammers GJ, Roos RA. Sleep and circadian rhythm alterations correlate with depression and cognitive impairment in Huntington's disease. Parkinsonism Relat Disord. 2010;16(5):345–350.
Gosselin N, Lassonde M, Petit D, Leclerc S, Mongrain V, Collie A, Montplaisir J. Sleep following sport-related concussions. Sleep Med. 2009;10(1):35–46.
HÖgl B, Arnulf I, Comella C, Ferreira J, Iranzo A, Tilley B, Trenkwalder C, Poewe W, Rascol O, Sampaio C, Stebbins GT, Schrag A, Goetz CG. Scales to assess sleep impairment in Parkinson's disease: critique and recommendations. Mov Disord. 2010;25(16):2704–2716.
Towns SJ, Silva MA, Belanger HG. Subjective sleep quality and post concussion symptoms following mild traumatic brain injury. Brain Inj. 2015;29(11):1337–1341.
Videnovic A, Leurgans S, Fan W, Jaglin J, Shannon KM. Daytime somnolence and nocturnal sleep disturbances in Huntington disease. Parkinsonism Relat Disord. 2009;15(6):471–474.