Background
Methods
Sample
Instruments
Data analysis
Results
Descriptive characteristics of the sample
Subsample dementia | Full sample | |
---|---|---|
Characteristics | n (%) | n (%) |
PWD | ||
Sex | ||
Male | 204 (46.3) | 682 (47.8) |
Female | 237 (53.7) | 746 (52.2) |
Age | ||
< 73 | 68 (15.4) | 352 (24.6) |
73–78 | 102 (23.1) | 334 (23.4) |
79–83 | 141 (32.0) | 352 (24.6) |
> 83 | 130 (29.5) | 390 (27.3) |
Ethnicity | ||
White/White British | 415 (94.5) | 1343 (94.0) |
Other ethnicity | 24 (5.5) | 78 (5.5) |
Missing | 2 | 7 |
Deprivation quintilesa | ||
1 – least deprived | 125 (28.9) | 349 (24.9) |
2 | 96 (22.2) | 299 (21.4) |
3 | 78 (18.0) | 280 (20.0) |
4 | 70 (16.2) | 253 (18.1) |
5 – most deprived | 64 (14.8) | 219 (15.6) |
Missing | 8 | 28 |
Number of comorbiditiesb | ||
0 | 96 (21.8) | 315 (22.1) |
1 | 121 (27.4) | 376 (26.3) |
2 | 107 (24.3) | 332 (23.2) |
3 | 71 (16.1) | 232 (16.2) |
4 or more | 46 (10.4) | 173 (12.2) |
Missing | 0 | 6 |
Carers: | ||
Sex | ||
Male | 110 (32.2) | 312 (30.5) |
Female | 232 (67.8) | 710 (69.5) |
Age (y) | ||
< 57 | 75 (21.9) | 245 (24.0) |
57–67 | 74 (21.6) | 254 (24.9) |
68–76 | 90 (26.3) | 272 (26.6) |
> 76 | 103 (30.1) | 251 (24.6) |
Ethnicity | ||
White/White British | 323 (95.6) | 958 (95.2) |
Other ethnicity | 15 (4.4) | 48 (4.8) |
Missing | 4 | 16 |
Relationship | ||
Husband/wife/partner | 214 (63.1) | 615 (61.0) |
Son/daughter | 94 (27.7) | 295 (29.2) |
Son/daughter-in-law | 11 (3.2) | 25 (2.5) |
Sibling | 6 (1.8) | 14 (1.4) |
Other relative | 6 (1.8) | 28 (2.8) |
Friend | 3 (0.9) | 16 (1.6) |
Neighbour | 3 (0.9) | 7 (0.7) |
Other | 2 (0.6) | 9 (0.9) |
Missing | 3 | 13 |
Living with relative/friend | ||
Yes | 237 (70.3) | 683 (68.0) |
No | 100 (29.7) | 321 (32.0) |
Missing | 5 | 18 |
Targeting
Ordering of item thresholds
Item fit
Subsample dementia | Full sample | |||||||||
---|---|---|---|---|---|---|---|---|---|---|
Item | Location | Fit Residual | ChiSq |
p
| DIF | Location | Fit Residual | ChiSq |
p
| DIF |
2. Worried or anxious | 0.331 | 1.081 | 5.84 | 0.44 |
ns
| 0.349 | 0.886 | 3.54 | 0.94 |
ns
|
4. Frustrated | 0.483 | 0.338 | 4.58 | 0.60 |
ns
| 0.546 | 0.257 | 2.66 | 0.98 |
ns
|
7. Sad | 0.036 | − 0.416 | 4.23 | 0.65 |
ns
| 0.080 | −0.255 | 6.58 | 0.68 |
ns
|
8. Lonely | − 0.238 | 1.948 | 19.47 | 0.00 |
ns
| −0.206 | 2.222 | 5.59 | 0.78 |
ns
|
9. Distressed | −0.531 | − 0.252 | 2.31 | 0.89 |
ns
| −0.391 | −2.395 | 7.04 | 0.63 |
ns
|
11. Irritable | 0.050 | 0.497 | 3.16 | 0.79 |
ns
| 0.007 | 0.361 | 1.66 | 1.00 |
ns
|
12. Fed-up | 0.489 | 0.192 | 3.69 | 0.72 |
ns
| 0.425 | 0.361 | 2.20 | 0.99 |
ns
|
13. Things you wanted but couldn’t | 0.735 | 2.408 | 21.20 | 0.00 |
ns
| 0.829 |
4.077
| 12.51 | 0.19 |
ns
|
14. Forgetting happened recently | 0.673 | −0.974 | 11.45 | 0.08 |
ns
| 0.654 | −1.100 | 4.43 | 0.88 |
ns
|
15. Forgetting who people are | 0.018 | −0.207 | 6.34 | 0.39 |
ns
| −0.043 |
2.511
| 6.68 | 0.67 |
ns
|
16. Forgetting what day it is | 0.375 | 1.342 | 5.28 | 0.51 |
ns
| 0.135 |
4.339
| 11.45 | 0.25 |
ns
|
17. Thoughts being muddled | 0.280 | −1.107 | 11.45 | 0.08 |
ns
| 0.126 | −2.376 | 8.27 | 0.51 |
ns
|
18. Difficulty making decisions | −0.123 | −1.527 | 8.23 | 0.22 |
ns
| −0.103 |
− 2.777
| 8.08 | 0.53 |
ns
|
19. Poor concentration | 0.305 |
−2.557
| 16.96 | 0.01 |
ns
| 0.298 | −2.338 | 6.86 | 0.65 |
ns
|
20. Not having enough company | −0.468 | 1.750 | 16.53 | 0.01 |
ns
| −0.415 | −0.981 | 5.01 | 0.83 |
ns
|
21. Get on with people close to you | −0.366 | −2.134 | 10.65 | 0.10 |
ns
| −0.422 | −1.291 | 5.21 | 0.82 |
ns
|
22. Getting the affection you want | −0.564 | −1.112 | 6.15 | 0.41 |
ns
| −0.525 | 0.328 | 6.63 | 0.68 |
ns
|
23. People not listening to you | −0.635 | 0.290 | 5.56 | 0.47 |
ns
| −0.479 | −0.989 | 5.73 | 0.77 |
ns
|
24. Making yourself understood | −0.319 | −1.278 | 6.88 | 0.33 | PWD sex | −0.337 | −1.792 | 4.27 | 0.89 |
ns
|
25. Getting help when needed | −0.466 | −1.278 | 11.54 | 0.07 |
ns
| −0.511 |
−2.833
| 5.07 | 0.83 |
ns
|
26. Getting to the toilet in time | −0.202 | 1.596 | 16.87 | 0.01 |
ns
| −0.267 |
3.543
| 17.96 | 0.04 |
ns
|
27. How you feel in yourself | 0.011 |
−2.538
| 16.88 | 0.01 |
ns
| 0.016 |
−4.440
| 14.24 | 0.11 |
ns
|
28. Overall health | 0.125 | −0.816 | 5.74 | 0.45 |
ns
| 0.232 | −1.848 | 6.27 | 0.71 |
ns
|
Subsample dementia | Full sample | |||||||||
---|---|---|---|---|---|---|---|---|---|---|
Item | Location | Fit Residual | ChiSq |
p
| DIF | Location | Fit Residual | ChiSq |
p
| DIF |
2. Worried or anxious | 0.456 | − 0.264 | 6.83 | 0.34 |
ns
| 0.637 | 0.278 | 3.76 | 0.93 |
ns
|
3. Frustrated | 0.502 | − 0.052 | 4.28 | 0.64 |
ns
| 0.574 | −0.677 | 4.27 | 0.89 |
ns
|
5. Sad | − 0.464 | − 0.175 | 13.58 | 0.03 |
ns
| −0.330 | −1.455 | 7.01 | 0.64 |
ns
|
7. Distressed | −0.532 | −1.198 | 6.24 | 0.40 |
ns
| −0.425 | −2.095 | 6.48 | 0.69 |
ns
|
9. Irritable | 0.000 | 0.985 | 14.32 | 0.03 | PWD sex | 0.052 | 0.919 | 3.07 | 0.96 | PWD sex PWD age Relation |
10. Fed-up | 0.216 | −0.266 | 13.69 | 0.03 |
ns
| 0.287 | −1.249 | 3.05 | 0.96 |
ns
|
12. Memory in general | 0.623 | 1.094 | 4.72 | 0.58 |
ns
| 0.664 | 1.529 | 6.49 | 0.69 |
ns
|
13. Forgetting that happened long ago | −0.610 |
2.793
| 12.90 | 0.04 |
ns
| −0.467 |
4.704
| 19.16 | 0.02 |
ns
|
14. Forgetting that happened recently | 1.507 | −0.172 | 5.16 | 0.52 |
ns
| 1.462 | 0.373 | 4.66 | 0.86 |
ns
|
15. Forgetting people’s names | 0.755 | 0.478 | 2.61 | 0.86 |
ns
| 0.684 |
2.627
| 8.42 | 0.49 |
ns
|
16. Forgetting where he/she is | −0.754 | 0.399 | 9.51 | 0.15 |
ns
| −0.866 | −0.539 | 5.87 | 0.75 |
ns
|
17. Forgetting what day it is | 0.632 | 1.541 | 2.52 | 0.87 |
ns
| 0.451 | 2.045 | 4.86 | 0.85 | Severity |
18. Thoughts being muddled | 0.732 | −2.251 | 21.98 | 0.00 | Carer age Relation | 0.604 |
−3.813
| 25.07 | 0.00 |
ns
|
19. Difficulty making decisions | 0.535 | −1.790 | 17.28 | 0.01 |
ns
| 0.458 |
−3.475
| 15.15 | 0.09 |
ns
|
20. Making him/herself understood | −0.253 | 0.748 | 13.65 | 0.03 |
ns
| −0.201 | 2.456 | 3.60 | 0.94 |
ns
|
21. Keeping him/herself clean | −0.685 | 2.373 | 17.93 | 0.01 |
ns
| −0.744 | 2.423 | 7.96 | 0.54 |
ns
|
22. Keeping him/herself looking nice | −0.746 | 1.470 | 17.92 | 0.01 |
ns
| −0.702 | 2.008 | 9.74 | 0.37 |
ns
|
23. Getting from the shops | −0.436 | −0.795 | 3.45 | 0.75 |
ns
| −0.501 | −0.922 | 3.61 | 0.94 |
ns
|
24. Using money to pay | −0.411 | −0.573 | 4.80 | 0.57 |
ns
| −0.578 | −1.365 | 5.59 | 0.78 |
ns
|
25. Looking after finances | −0.161 | 1.300 | 7.54 | 0.27 |
ns
| −0.304 | 0.915 | 9.25 | 0.41 |
ns
|
26. Things taking longer | 0.378 | −1.195 | 8.67 | 0.19 |
ns
| 0.402 |
−2.987
| 13.39 | 0.15 |
ns
|
27. Getting in touch with people | −0.376 | −0.843 | 7.23 | 0.30 |
ns
| −0.472 | −1.684 | 6.39 | 0.70 |
ns
|
28. Not having enough company | −0.446 | 1.012 | 6.61 | 0.36 | PWD sex PWD age Carer age Relation | −0.352 | 2.197 | 7.79 | 0.56 | PWD sex Carer age Relation |
29. Not being able to help other people | −0.542 | 0.012 | 4.29 | 0.64 |
ns
| −0.472 | 1.136 | 5.80 | 0.76 |
ns
|
30. Not playing a useful part | −0.281 | −0.383 | 7.64 | 0.27 |
ns
| −0.231 | −2.067 | 8.27 | 0.51 |
ns
|
31. His/her physical health | 0.360 | 0.783 | 10.10 | 0.12 |
ns
| 0.369 |
2.762
| 9.22 | 0.42 |
ns
|