Table 4

Fit statistics and hierarchy of the disability items

	Activity	Infit MnSq	Outfit MnSq	Location	SE
Stooping, kneeling or crouching	Mobility	1.04	1.00	−3.56	0.02
Climbing several flights of stairs without resting	Mobility	1.02	0.98	−3.36	0.02
Lifting or carrying weights over 10 pounds/5 kilos, like a heavy bag of groceries	Mobility	0.99	0.96	−2.57	0.02
Getting up from a chair after sitting for long periods	Mobility	1.08	1.10	−2.24	0.02
Pulling or pushing large objects like a living room chair	Mobility	0.97	0.91	−1.66	0.02
Climbing 1 flight of stairs without resting	Mobility	1.02	0.98	−1.22	0.02
Sitting for about 2 hours	Mobility	1.38	1.76	−1.07	0.03
Walking 100 m	Mobility	0.93	0.84	−1.05	0.03
Doing work around the house or garden	IADL	0.89	0.74	−1.04	0.03
Reaching or extending your arms above shoulder level	Mobility	1.21	1.44	−0.78	0.03
Dressing, including putting on shoes and socks	ADL	0.99	0.78	−0.21	0.03
Using a map to figure out how to get around in a strange place	IADL	1.14	1.05	0.04	0.03
Shopping for groceries	IADL	0.80	0.43	0.23	0.03
Bathing or showering	ADL	0.79	0.41	0.46	0.04
Getting into or out of bed	ADL	0.95	0.45	0.97	0.04
Managing money, such as paying bills and keeping track of expenses	IADL	1.00	0.50	1.23	0.04
Picking up a small coin from a table	Mobility	1.19	0.69	1.31	0.04
Preparing a hot meal	IADL	0.81	0.29	1.41	0.05
Using the toilet, including getting up or down	ADL	0.83	0.21	2.06	0.06
Walking across a room	ADL	0.82	0.17	2.21	0.06
Making telephone calls	IADL	0.93	0.20	2.83	0.07
Eating, such as cutting up your food	ADL	0.93	0.20	2.96	0.08
Taking medications	IADL	0.90	0.17	3.06	0.08

Item difficulty, items ordered according to the expected hierarchy of difficulty from the easiest to endorse (stopping, kneeling or crouching=−3.56) to the most difficult (taking medications=3.06 logits).
ADL, activities of daily living; IADL, instrumental activities of daily living; MnSq, mean square residual.