MSLT

MSLT stands for Multiple Sleep Latency Test . It is a sleep study used to assess daytime sleepiness and diagnose conditions like narcolepsy and idiopathic hypersomnia. It measures how quickly a person falls asleep during scheduled naps and whether they enter REM (rapid eye movement) sleep. 

An MSLT test is always preceded by an overnight sleep study (in the lab) and 2 weeks of actigraphy testing.

---

MWT

MWT stands for Maintenance of Wakefulness Test. It’s a sleep test used to assess a person’s ability to stay awake during specific periods in a comfortable, quiet, and dark environment. The test is often used to evaluate the effectiveness of treatments for sleep disorders that cause excessive daytime sleepiness, like sleep apnea or narcolepsy. 

An MWT is not usually preceded by an in-lab test.