The Global Assessment Questionnaire (GSAQ) can be used in primary care settings to screen for sleep disorders. It is easily administered and can help suggest possible causes for the sleeping difficulties. The authors are from 6 medical center sleep laboratories in the United States, with the research supported by Pharmacia Corporation.
NOTE: A copy of the questionnaire is available from Dr Roth (troth1@hfhs.org ) . The questionnaire is under copyright from Pharmacia Corporation.
Background information:
(1) employment status, especially night or rotating shift work
(2) major or stressful event during the past month that has affected sleep
There are 11 questions based on sleep-related experiences during the past 4 weeks.
where:
• Question 10 has 5 separate responses, giving a total of 15 responses.
Responses are by a 4 point Likert scale from 0 to 3 (never, sometimes, usually, always).
total score =
= SUM(points for all 15 items)
Interpretation:
• minimum total score: 0
• maximum total score: 45
• In the paper by Roth et al (2002) the authors describe the use of subscores and logistic regression equations to give a probability for common causes of disordered sleep (primary insomnia, mental disorder related, obstructive sleep apnea, restless leg syndrome, periodic limb movement, parasomnia, shift work). The equations have not been published to our knowledge.
• Looking at the list of questions, the subquestions for question 10 include items not covered by the common conditions listed by Roth (see table below). I have also added alcohol use to 10d.
• Some authors distinguish between mental (stress, worry, etc.) and psychiatric causes of disordered sleep.
• Parasomnia covers a fairly wide range of conditions.
• I assume that primary insomnia would be diagnosed if there is evidence of disordered sleep but no secondary causes are elicited.
• Many patients may show more than 1 cause (mixed).
|
Questions |
Usefulness |
|
1, 2, 3 |
establish disordered sleep |
|
4 |
may indicate work-related, especially with history of shift or night work |
|
5 and 6 |
obstructive sleep apnea |
|
7 |
restless legs syndrome |
|
8 |
periodic limb movement |
|
9 |
parasomnias |
|
10a and 10b |
physical or illness related |
|
10c |
mental disorder related |
|
10d |
drug-related |
|
10e |
variable depending on response |
|
11 |
mental disorder related |
Performance:
• Test-retest reliability ranged from 0.51 to 0.92
• Sensitivity for the various disorders ranged from 79% to 100%, while the specificity was about 50%.
Limitations:
• The International Classification of Sleep Disorders (see the table in Coleman) lists over 80 disorders affecting sleep. The questionnaire could help with initial evaluation in the primary care setting, but some patients will require a more extensive evaluation with sleep studies.
• Without access to the logistic regression equations it would be hard to reproduce the study as reported.
• I would have included a "rarely" response category.
Specialty: Neurology
