Skip to main content

Advertisement

Table 5 13-item SFInX: item fit and difficulty (ordered by misfit (INFIT MNSQ) of items to the Rasch model)

From: The Shoulder Function Index (SFInX): a clinician-observed outcome measure for people with a proximal humeral fracture

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