Pittsburgh Sleep Quality Index
The Pittsburgh Sleep Quality Index (PSQI) was developed by Dr. Daniel J. Buysse and coworkers at the University of Pittsburgh’s Western Psychiatric Institute and Clinic in the late 1980s.
The PSQI was created after observation that most patients with psychiatric disorders also have sleep disorders. The questionnaire has nineteen individual items which are used to generate seven composite scores. The results give numbers in seven categories: subjective sleep quality, sleep latency, sleep duration, habitual sleep efficiency, sleep disturbances, use of sleeping medication, and daytime dysfunction These numbers can be useful to psychiatrists and other doctors in calling out the nuances of the patient’s sleep disorders and patterns.
The assessment takes about five to ten minutes to administer and score, a scoring process that does not require formal training. As with the other sleep-related scales, the PSQI is best used as a screening tool to identify patients that may require further sleep testing. While the global PSQI score is rather good at identifying the likely presence of sleep disorders (http://www.ncbi.nlm.nih.gov/pubmed/12217446), , its seven composite scores are less useful clinically. It is unclear whether the PSQI can be used to follow a patient’s response to treatment.
At least one critic has suggested http://onlinelibrary.wiley.com/doi/10.1111/j.1479-8425.2008.00371.x/abstract that adjusting the test to provide 2 or 3 different scores would provide a more accurate picture of the patient’s condition.
The patient is responsible for answering the questions from his or her subjective experience over the previous month. There is no machine evaluation of response time or sleepiness.
It has also been shown that the PSQI is not effective for evaluating sleep quality in patients with dementia - http://www.ncbi.nlm.nih.gov/pubmed/19337985?dopt=Abstract
The Pittsburgh Sleep Medicine Clinic also created the Pittsburgh Insomnia Rating Scale, although this has found less use than the PSQI.