Sleep Med Psychophysiol.  2004 Dec;11(2):80-83.

Changes in Multiple Sleep Latency Test Results according to Different Criteria of Sleep Onset

• Lim SW
• Bok KN
• Lee HJ
• Kim L

Abstract

OBJECTIVES
The multiple sleep latency test (MSLT) is commonly used as a valid objective measure of sleepiness. The procedure of MSLT is well standardized but the sleep onset criterion is somewhat variable. One epoch of stage 1 sleep is the most commonly used criterion, and the criterion of three epochs of stage 1 sleep is also used. The purpose of this study was to compare the two criteria used to determine sleep onset. METHODS: We retrospectively analyzed 60 consecutive MSLT that were performed according to a standaridized protocol. We scored each test using the two different criteria for sleep onset and then statistically analyed the results. RESULTS: Using the different criteria, 20 patients among 60 showed changes in mean sleep latency (33.3%). The extent of change ranged from 1.3% to 38.5% (mean 15.9%). Non-narcoleptic patients showed a significantly higher incidence of change than other sleep disorder patients. CONCLUSION: Changes in mean sleep latency occurred according to the different criteria of sleep onset. But the difference arising from different criteria was statistically not significant in patients with moderate to severe sleepiness. Considering that 1 epoch criterion for sleep onset is more sensitive in detecting clinically significant sleepiness, the authors suggest that the 1 epoch criterion is more reliable than the 3 epochs criterion.

Keyword

Multiple sleep latency test (MSLT) ; Sleep onset criterion

MeSH Terms

Humans
Incidence
Retrospective Studies