Psychometric properties of Turkish version of Jenkins sleep scale in fibromyalgia syndrome

Fibromyalgia syndrome (FMS) has adverse effects on the quality of sleep. The aim of this study was to investigate the validity and reliability of Jenkins Sleep Scale (JSS-TR) in Turkish FMS patients.

FMS patients who met the 2016 fibromyalgia diagnostic criteria were included in the study. Clinical and demographic data of the patients were noted. The relationship between this scale and other functional parameters such as Pittsburgh Sleep Quality Index (PSQI), European Quality of Life Scale-5 Dimensions (EQ-5D), Fatigue Severity Scale (FSS), Beck Depression Inventory (BDI) was examined. Fibromyalgia Impact Questionnaire (FIQ) was used to evaluate the functional status of the patients and the progression of the disease. Test-retest reliability was calculated by re-applying the questionnaire to patients at 2-week intervals. Duloxetine treatment was initiated in newly diagnosed patients and sensitivity to change was tested at the end of the treatment. Spearman correlation coefficient was used. P < 0.05 was accepted as significant.

Eighty-one FMS patients (71 females, 10 males) were included in the study. The mean age was 44.2 ± 10.7 years. The strongest correlation of JSS-TR was with another sleep questionnaire, PSQI (rho = 0.79, p < 0.0005). The correlation with other functional parameters and FIQ was moderate. In test-retest validity, intraclass correlation coefficient was found to be 0.98 (p < 0.0005). Chronbach α value calculated for internal consistency was found to be 0.741.

JSS-TR is a valid, simple and feasible sleep instrument that can be easily applied to FMS patients both in researches and clinical settings.