Dimensionality, psychometric properties, and population-based norms of the Turkish version of the Chalder Fatigue Scale among adults

Table 3 Test–retest reliability and internal consistency of the Chalder Fatigue Scale

	κ	ICC	95% CI		Cronbach’s α if item deleted	r
	κ	ICC	Lower	Upper	Cronbach’s α if item deleted	r
1. Do you have problems with tiredness?	0.33		0.20	0.44	0.848	0.60
2. Do you need to rest more?	0.21		0.10	0.32	0.856	0.48
3. Do you feel sleepy or drowsy?	0.32		0.20	0.45	0.846	0.63
4. Do you have problems starting things?	0.22		0.15	0.33	0.847	0.61
5. Do you lack energy?	0.40		0.29	0.51	0.840	0.70
6. Do you have less strength in your muscles?	0.45		0.33	0.56	0.847	0.61
7. Do you feel weak?	0.21		0.10	0.32	0.842	0.67
CFS-PF			0.67
8. Do you have difficulty concentrating?	0.22		0.10	0.34	0.848	0.60
9. Do you make slips of the tongue when speaking?	0.42		0.29	0.55	0.863	0.39
10. Do you find it more difficult to find the correct word?	0.33		0.20	0.46	0.858	0.46
11. How is your memory?	0.34		0.20	0.49	0.863	0.37
CFS-MF		0.67	0.55	0.76
CFS			0.68	0.83

κ: Weighted kappa coefficient, ICC: intraclass correlation coefficient, CI: Confidence interval, r: Pearson correlation coefficient for item-total correlation, CFS-PF: Chalder Fatigue Scale-Physical Fatigue, CFS-MF: Chalder Fatigue Scale-Mental Fatigue, CFS: Chalder Fatigue Scale

ISSN: 1477-7525