Correlate as named by investigatorPeople investigatedFinding
Sleep quality
50-69 aged women, France, 1975
Sleep disturbances
Retirees, Southern California, USA, followed 9 months199?
Sleep Quality
Employed females, USA , 2004
Difficulty with sleeping
70+aged, Hong Kong, 1991-1992
Sleep
60+ aged, Hong Kong, 2000
Sleep problems
16+ aged, general public, UK, 2000
Sleeping problems
Community dwelling seniors, Vancouver, Canada, 1987-88