In order to assess habitual sleep patterns
and depressive symptoms, participants completed the Pittsburgh
Sleep Quality Index (PSQI; Buysse et al., 1989) and the
Beck Depression Inventory-II(BDI-II; Beck et al., 1996),respectively.
The PSQI and BDI-II are widely used and well-validated
instruments (Carpenter and Andrykowski, 1998; Dozois et al.,
1998)