Skip to main content
Intermediate Technical IVT

MSLT

Also written as: MSLT — Multiple Sleep Latency Test

Multiple Sleep Latency Test; standardized assessment measuring the tendency to fall asleep during daytime conditions.

Full Definition

The Multiple Sleep Latency Test (MSLT) is a standardized objective assessment of daytime sleepiness and the tendency to enter REM sleep. The test consists of four to five 20-minute nap opportunities scheduled at two-hour intervals throughout the day following an overnight sleep study. Key measurements include sleep latency (time to fall asleep) and REM latency (time to enter REM sleep). The MSLT is essential for diagnosing narcolepsy, idiopathic hypersomnia, and other disorders of excessive daytime sleepiness, with specific criteria established for different sleep disorders.

Usage

Usage note: Must follow overnight polysomnography and requires strict protocol adherence.

In Context

  • "The MSLT revealed a mean sleep latency of 3 minutes with REM sleep in three of five naps, confirming narcolepsy." — Sleep disorder evaluation
  • "MSLT results showed severe daytime sleepiness but no sleep-onset REM periods." — Hypersomnia assessment

Also known as

Multiple Sleep Latency Test daytime sleep study

Contrasted with

MWT overnight sleep study

Don't confuse with

MWT CPAP titration study

Editors from these organisations have used our services since 1998

Reuters BBC Oxford University Press Penguin Random House Springer Microsoft Suncor Energy United Nations Fisher Investments IBM The Home Depot KODAK CHEVRON