Questionnaires
BAI
Cutoff > 7
BDI
Curoff > 9
Also 0–13: minimal depression; 14–19: mild depression; 20–28: moderate depression; and 29–63: severe depression
Epworth
Cutoff > 9
Wikipedia
PSQI
Cutoff > 5
PSQI.doc
Original paper, with scoring at end
Buysse 1989 - PSQI scoring.pdf