Psychometric Properties of the Brief Version of Pittsburgh Sleep Quality Index (B-PSQI) among Shift Workers on Non-24-h Working and Rest Schedules

Sleep problems among shift workers have emerged as a public health concern in recent years. However, few validation studies of self-reported sleep quality questionnaires were performed among shift workers. The present study aimed to examine the psychometric properties of the brief version of Pittsburgh Sleep Quality Index (B-PSQI) in a shift workers sample. In total, 443 male sailors were recruited, of whom 46.95% (n = 208) were watchstanding sailors on 18-h working schedule at sea. All participants completed the B-PSQI, the Insomnia Severity Index (ISI), the Self-rating Depression Scale (SDS), and Self-rating Anxiety Scale (SAS) before and after a 30-day saling. 40 watchstanding sailors were selected to wear wrist actigraphy throughout the sailing. The result showed that the B-PSQI had acceptable internal consistency reliability in different sailor groups. Confirmatory factor analysis showed optimal fit of the single-factor model of the B-PSQI in different sailor groups. Futhermore, scalar invariance between watchstanding and day-working sailors was supported, as well as longitudinal scalar invariance across time. In addition, receiver operating characteristic (ROC) analysis showed that the B-PSQI yields high discrimination power to detect poor sleep quality using ISI ≥ 8 criterion. However, a lack of inter-method agreement across the B-PSQI and actigraphy was found in this study. Moreover, the total scores of B-PSQI were positively related to depression and anxiety symptoms in the present sample. In conclusion, the B-PSQI is a reliable and valid sleep quality measure and a useful screening tool for sleep disorders among shift workers.