The Pittsburgh Sleep Quality Index (PSQI) Applied to Cancer Patients: Psychometric Properties and Factors Affecting Sleep Quality.

AbstractObjectiveMethodsResultsConclusionsCancer patients frequently report sleep problems. The Pittsburgh Sleep Quality Index (PSQI) is a 19-item instrument for assessing sleep problems. The main objective of this study was to analyze the usefulness of the PSQI in oncological research.A sample of 1,733 cancer patients with mixed diagnoses were included. In addition to the PSQI, the following questionnaires were adopted: the Insomnia Severity Index (ISI), the Jenkins Sleep Scale (JSS) and the sleep scale of the EORTC QLQ-SURV100.The internal consistency of the PSQI was α = 0.79. Of the PSQI subscales, the subjective sleep quality correlated most strongly with the other sleep instruments (<italic>r</italic> between 0.68 and 0.77). In total, 69.2% of the sample were poor sleepers; the effect size of the difference between the PSQI total scores of the patients and a general population sample was <italic>d</italic> = 0.83. Female patients experienced more sleep problems than male patients (<italic>d</italic> = −0.49), and younger patients (<60 years) reported more sleep problems than older patients (≥60 years) (<italic>d</italic> = 0.21).The PSQI can be recommended for use in clinical practice since its sub-dimensions provide detailed information on the sleep situation of cancer patients. [ABSTRACT FROM AUTHOR]