Table 5.

Goodness of fit to the Rasch Model of the COVID-19 Pandemic Fatigue Scale (CPFS) in the COVID-19 Snapshot Monitoring (COSMO)-Spain study, November 2020.

Attribute		Criteria	CPFS
Item fit residual
	Mean	0	–.189
	SD	1	.852
Person fit residual
	Mean	0	–.285
	SD	1	.736
Item-trait, χ2 (df)		Low	42.025 (24)
Interaction P value		NSa	.0128
PSIb		>0.70	.642
Unidimensionality
	Independent t tests	<5%	2.00%
	95% CI binomial	*c	.042-.091

^aNS: nonsignificant.

^bPSI: Personal Separation Index

^cLower bound should be ≤.05.