Table 1. Multilevel, linear mixed model of the relationship between menstrual phase and sleeping WST.

	Unstandardized b-coefficient	S.E.M.
Intercept	35.06	0.10
Cycle phase
Menstrual	Reference	Reference
Follicular	−0.01	0.04
Fertile	−0.13*	0.02
Early-luteal	0.24*	0.02
Late-luteal	0.37*	0.03

*refers to P<0.001.