The phrase "a combination of sleep" is correct and usable in written English.
It can be used when discussing different types or aspects of sleep that are being mixed or integrated together.
Example: "After a long week, I found that a combination of sleep and relaxation was essential for my recovery."
Alternatives: "a mix of sleep" or "a blend of sleep".
A combination of sleep deprivation and Richard Curtis.
It's probably related to a combination of sleep deprivation and added stress".
A combination of sleep deprivation and the angelic glow of my smartphone screen gave the crib a nearly Messianic quality.
Non-motor clinical symptoms of PD refer to a combination of sleep disturbances, autonomic dysfunction, sensory complications, olfactory deficits, and neuropsychiatric problems.
Prestwich and colleagues found that receiving a combination of sleep health education and keeping sleep logs resulted in a mean improvement of approximately 54 minutes of sleep per night among participants in their sample of college students [ 46].
Another experimental study in healthy volunteers found that a combination of sleep restriction and circadian disruptions for 3 weeks resulted in impaired glucose tolerance with a 32% reduction in insulin response to a standardized meal (6).
A combination of partial sleep restriction ("wake therapy"), phase-advancing the timing of sleep (and awakening), and morning bright light have an enhanced and almost immediate antidepressant action, but there are insufficient comparative controlled trials to prove that this innovative triple combination is more antidepressant than bright light treatment alone.
At follow-up, 13.4% (n = 18) of the adolescents suffered from a combination of several sleep disturbances (two or more of the following: insomnia, hypersomnia, sleep-wake rhythm disturbance).
Then he said, "Well, it's a combination of the sleep surface materials and the peace of mind that comes from it being a Vera Wang".
I had always been very athletic, but a combination of no sleep, late night food, too much alcohol and stress that I didn't acknowledge started to take its toll.
"It was a combination of not sleeping well and ruminating and dwelling on the frustration of not sleeping".
