Table 5.

Results of the differential item functioning analyses.

Eating Assessment Tool Item	Gender Females (n=79) vs Males (n=48)		Aspiration No aspiration (n=21) vs Aspiration (n=106)		Oral intake Normal (n=76) vs Abnormal (n=49)
	DIF contrast	Rasch-Welch probability	DIF contrast	Rasch-Welch probability	DIF contrast	Rasch-Welch probability
1. My swallowing problem has caused me to lose weight.	0.00	1.000	0.00	1.000	0.28	0.1751
2. My swallowing problem interferes with my ability to go out for meals.	0.25	0.1855	0.48*	0.0449*	0.60*	0.0018*
3. Swallowing liquids takes extra effort.	0.18	0.3496	0.33	0.1609	−0.11	0.5427
4. Swallowing solids takes extra effort.	0.00	1.000	0.03	0.8954	0.31	0.0972
5. Swallowing pills takes extra effort.	−0.21	0.2412	−0.52*	0.0280*	−0.03	0.8842
6. Swallowing is painful.	−0.14	0.5417	−0.87*	0.0047*	−0.48*	0.0303*
7. The pleasure of eating is affected by my swallowing.	0.15	0.4007	0.53*	0.0433*	0.35	0.0606
8. When I swallow food sticks in my throat.	0.19	0.2884	−0.06	0.7870	−0.30	0.0945
9. I cough when I eat.	−0.07	0.6867	0.04	0.8691	−0.40	0.0263*
10. Swallowing is stressful.	−0.32	0.0810	−0.15	0.5210	−0.23	0.2006

DIF=differential item functioning;

^*= |DIF contrast| ≥0.43 or p ≤ 0.05.