Validation of the Taiwanese version of the Athens insomnia scale and assessment of insomnia in Taiwanese cancer patients

Context: It is well known that insomnia is highly prevalent in cancer patients. Although various studies have used the Athens Insomnia Scale (AIS) for insomnia assessment, it has never been applied to cancer patients with insomnia. Objectives: The purpose of this study was to establish the reliability and validity of the Taiwanese AIS version (AIS-T) and evaluate the severity of insomnia among cancer patients in Taiwan. Methods: Using a cross-sectional research design, 195 cancer patients (n = 195) were recruited from outpatient oncology clinics. Results: Cronbach's alpha for internal consistency was 0.83, and the test-retest reliability was 0.94 over an interval of three days, based on a sample of 30 patients. Moreover, concurrent validity could be evaluated by significant correlations of the AIS-T with the Pittsburgh Sleep Quality Index-Taiwan form (PSQI-T) (r = 0.82, P < 0.001) and sleep efficiency measured by Actiwatch parameters (r = -0.54, P < 0.001). Construct validity could be established by the Brief Fatigue Inventory-Taiwan form (r = 0.56, P < 0.001) and Medical Outcomes Study Short Form-36-Taiwanese version (physical component summary: r = -0.52, P < 0.001; mental component summary: r = -0.53, P < 0.001). The AIS-T could detect significant known-group validity from sleep quality (PSQI-T ≥5 or <5, respectively). The Actiwatch parameters are consistent with the results of the AIS-T, and both data sets indicate that patients experienced sleep disturbances. The prevalence of insomnia, as defined by the criteria of the American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders, 4th ed., was 22.56%; 49.2% subjects had significant insomnia at the score ≥6 at AIS-T. Conclusion: This study concludes that the AIS-T is a reliable and valid instrument for assessing insomnia among cancer patients in Taiwan.