Table 2 Proportion of correct answers and respective 95% confidence interval (95%CI) for each statement, standardized loadings for the 2-factor latent trait model (LTM) and probability of correct answer in the 2 and 3-classes latent class model (LCM)
| Â | Â | Â | LTM | 2-classes LCM | 3-classes LCM | ||||
|---|---|---|---|---|---|---|---|---|---|
Statement (correct option) | Proportion of correct answers | One Factor | Two factor Model | Class 1 (52%) | Class 2 (48%) | Class 1 (31.1%) | Class 2 (28.1%) | Class 3 (40.9%) | |
| Â | % (95%CI) | Std.z1 | Std.z1 | Std.z2 | % | % | % | % | % |
1. A rheumatic disease is especially characterised by pain and stiffness in muscles and joints (t) | 82 (80-84) | 0.137 | 0.109 | 0.315 | 82 | 83 | 84 | 0.74 | 88 |
2. Rheumatic diseases are only seen in older women (f) | 87 (85-89) | -0.871 | 0.872 | 0.000 | 99 | 74 | 68 | 92 | 100 |
3. In general, rheumatic patients should rest as much as possible and move as little as possible (f) | 82 (80-83) | -0.735 | 0.703 | 0.060 | 95 | 68 | 63 | 85 | 95 |
4. Almost all rheumatic patients will finally end up in a wheelchair (f) | 71 (68-73) | -0.866 | 0.753 | -0.303 | 97 | 42 | 29 | 86 | 94 |
5. Medications for osteoarthritis cannot cure the disease, but can relieve pain and stiffness (t) | 93 (92-95) | 0.529 | -0.153 | 0.548 | 91 | 96 | 97 | 87 | 96 |
6. Glandular fever is a kind of rheumatic disease (f)* | 27 (25-29) | -0.408 | Â | Â | Â | Â | Â | Â | Â |
7. Rheumatoid arthritis is a rheumatic disease in which the joints are affected with inflammations (t) | 89 (87-90) | 0.027 | 0.265 | 0.581 | 90 | 88 | 90 | 79 | 96 |
8. Affected joints of rheumatic patients can be replaced with artificial joints (t) | 54 (52-57) | 0.285 | -0.089 | 0.333 | 48 | 61 | 65 | 41 | 56 |
9. Osteoarthritis (wear and tear) is the most common kind of rheumatic disease (t) | 88 (87-90) | 0.525 | -0.068 | 0.619 | 85 | 92 | 95 | 72 | 97 |
10. Multiple sclerosis (MS) is a rheumatic disease (f)* | 37 (34-39) | -0.655 | Â | Â | Â | Â | Â | Â | Â |
11. People can die from the consequences of rheumatic disease (t) | 47 (44-49) | 0.200 | -0.003 | 0.170 | 45 | 47 | 49 | 38 | 51 |
12. No kinds of rheumatic diseases can be cured (f) | 37 (35-39) | -0.387 | 0.332 | 0.062 | 45 | 29 | 27 | 34 | 49 |
13. Rheumatoid arthritis is caused by poor diet, and cold and damp weather (f) | 28 (25-30) | -0.680 | 0.529 | -0.099 | 41 | 13 | 08 | 34 | 39 |
14. Ankylosing spondylitis is a kind of rheumatic disease (t)* | 47 (45-50) | 0.131 | Â | Â | Â | Â | Â | Â | Â |
15. There are more than 100 different kinds of rheumatic diseases (t) | 66 (63-68) | 0.391 | -0.054 | 0.520 | 60 | 72 | 78 | 42 | 76 |
16. About one out of every twenty Portuguese people is being treated for a rheumatic disease (t) | 84 (82-86) | 0.613 | -0168 | 0.765 | 77 | 92 | 97 | 59 | 95 |
17. Fibromyalgia is a rheumatic disease (t)* | 38 (36-40) | 0.137 | Â | Â | Â | Â | Â | Â | Â |