Table 5.
A_irt item parameters
| Item parameters | |||||
| A_irt item | Discrim | Difficulty: location parameters | |||
| a |
b1 (se) |
b2 (se) |
b3 (se) |
b4 (se) |
|
| A1. What degree of difficulty do you have climbing up and down several flights of stairs? | 1.72 | -3.73 (0.59) |
-2.62 (0.29) |
-1.37 (0.14) |
0.21 (0.10) |
| A4. What degree of difficulty do you have bending to floor? | 1.91 | -2.54 (0.25) |
-1.58 (0.16) |
-0.32 (0.09) |
1.10 (0.12) |
| A5. What degree of difficulty do you have climbing up and down one flight of stairs?(*) | 1.91 | -2.76 (0.29) |
-1.64 (0.15) |
-0.07 (0.09) |
1.13 (0.13) |
| A6. What degree of difficulty do you have putting on socks/stockings? | 2.27 | -1.87 (0.17) |
-1.12 (0.11) |
-0.03 (0.07) |
0.96 (0.10) |
| A8. What degree of difficulty do you have rising from sitting? | 2.07 | -2.82 (0.34) |
-1.41 (0.13) |
0.34 (0.08) |
1.82 (0.17) |
| A10. What degree of difficulty do you have lifting? | 1.79 | -2.17 (0.21) |
-1.15 (0.12) |
0.24 (0.09) |
1.70 (0.17) |
| A11. What degree of difficulty do you have standing? | 1.41 | -2.90 (0.35) |
-1.41 (0.17) |
0.41 (0.12) |
2.20 (0.26) |
| A12. What degree of difficulty do you have walking on the flat ? | 1.47 | -3.27 (0.41) |
-1.57 (0.17) |
0.52 (0.12) |
2.42 (0.29) |
| A13. What degree of difficulty do you have taking off socks/stockings? | 2.34 | -1.79 (0.15) |
-0.89 (0.10) |
0.35 (0.07) |
1.14 (0.11) |
| A14. Do you use a walking stick? | 0.95 |
-1.21 (0.22) |
-0.43 (0.17) |
-0.20 (0.16) |
0.63 (0.18) |
| A15. What degree of difficulty do you have rising from bed? | 3.12 | -1.68 (0.13) |
-0.80 (0.08) |
0.66 (0.07) |
1.60 (0.11) |
| A16. What degree of difficulty do you have putting on/off shoes? | 2.29 | -1.29 (0.11) |
-0.37 (0.09) |
0.62 (0.08) |
1.51 (0.12) |
| A17. Does your health now limit you in these activities? Bending, kneeling or stooping | 1.02 |
-4.52 (1.24) |
-1.76 (0.34) |
||
| A18. What degree of difficulty do you have getting on/off toilet? | 2.80 | -1.36 (0.11) |
-0.35 (0.07) |
0.95 (0.08) |
1.97 (0.16) |
| A19. What degree of difficulty do you have lying in bed? | 2.21 | -1.24 (0.11) |
-0.30 (0.08) |
1.17 (0.11) |
2.23 (0.21) |
| A20. What degree of difficulty do you have sitting? | 2.76 | -1.19 (0.10) |
-0.26 (0.07) |
1.29 (0.10) |
2.63 (0.27) |
| A21. What degree of difficulty do you have dressing yourself (except shoes and socks)? | 2.71 | -0.51 (0.08) |
0.27 (0.07) |
1.78 (0.13) |
2.38 (0.23) |
| A22. What degree of difficulty do you have washing and drying yourself? | 2.53 | -0.43 (0.08) |
0.24 (0.07) |
1.70 (0.14) |
2.83 (0.35) |
| A23. What degree of difficulty do you have washing your hair? | 2.05 | 0.01 (0.08) |
0.60 (0.09) |
1.86 (0.17) |
2.78 (0.32) |
| A24. Do you need someone to help you go upstairs? | 1.63 | 0.21 (0.10) |
1.18 (0.14) |
1.64 (0.17) |
2.23 (0.24) |
| A25. Do you need someone to help you when you are walking? | 1.33 | 0.01 (0.11) |
1.56 (0.20) |
2.20 (0.27) |
3.27 (0.44) |
| A26. Do you need someone to help you go downstairs? | 1.59 | 0.25 (0.10) |
1.24 (0.14) |
1.66 (0.18) |
2.12 (0.23) |
| TOTAL | |||||
Key: Items in bold = items with low discrimination parameter (< 1.25).