Psychometric properties and accuracy of the European Portuguese version of the Pittsburgh Sleep Quality Index in clinical and non-clinical samples

To assess the reliability and validity concerning the formal European Portuguese version of the Pittsburgh Sleep Quality Index [PSQI (EP)], its accuracy, and optimal cut-off point. N = 564 volunteers (18–80 years old) recruited in several settings (e.g., university campuses; work place; home; sleep consultations), agreed to complete the PSQI (EP). Subgroups completed additional measures: Insomnia Severity Index (ISI), STOP-Bang, Glasgow Sleep...