Sleep onset latency

MSLT Scores
Minutes	Sleepiness
0–5	Severe
5–10	Troublesome
10–15	Manageable
15–20	Excellent

In sleep science, sleep onset latency (SOL) is the length of time that it takes to accomplish the transition from full wakefulness to sleep, normally to the lightest of the non-REM sleep stages.^[1]

^ The Corsini Encyclopedia of Psychology. John Wiley & Sons. 2010. ISBN 9780470170236.

[1] The Corsini Encyclopedia of Psychology. John Wiley & Sons. 2010. ISBN 9780470170236.

[1]