Table 5.

13-item SFInX: item fit and difficulty (ordered by misfit (INFIT MNSQ) of items to the Rasch model)

Item			PCM
No.	Name	Difficulty	INFIT		OUTFIT
		Logits (SE)	MNSQ	ZSTD	MNSQ	ZSTD
6	wash lower back	2.85 (0.23)	1.53	2.6	1.41	1.0
7	lying on affected side	−1.61 (0.27)	1.43	2.1	1.28	0.7
3	wash back shoulder	3.20 (0.24)	1.30	1.6	1.17	0.5
10	carry heavy object	−0.47 (0.22)	1.28	1.2	1.49	0.8
2	wash armpit	−1.53 (0.38)	1.27	1.2	1.58	0.9
8	reach behind for object	−0.12 (0.32)	1.15	0.9	0.83	−0.2
9	hold object arm by side	−1.53 (0.38)	0.84	−0.7	0.44	−0.7
12	hang up washing	2.34 (0.21)	0.82	−0.9	0.58	−0.7
4	comb hair	0.83 (0.22)	0.79	−1.4	0.72	−1.2
5	tuck in shirt	−1.29 (0.27)	0.78	−1.4	0.65	−1.5
13	throw ball overhead	1.66 (0.21)	0.66	−2.1	0.46	−1.4
11	lift object shoulder level	−1.00 (0.35)	0.64	−2.0	0.35	−0.9
1	drink from cup	−3.34 (0.56)	0.60	−1.1	0.14	−1.0
	Test mean	0.00 (0.30)	1.01	0.0	0.85	−0.3
	Test SD	1.93 (0.10)	0.31	1.6	0.46	0.9