Table 2.
Endorsement frequencies and Mokken scalability (Loevinger’s H i coefficients) for the 9 items of the Shared Decision-Making Questionnaire (SDM-Q-9)
| Item number and content | Mean (SD) | Endorsement frequencies (%) | H i | |||||
|---|---|---|---|---|---|---|---|---|
| 1 | 2 | 3 | 4 | 5 | 6 | |||
| 1. A decision needs to be made | 5.19 (1.37) | 14 (6) | 4 (2) | 3 (0.01) | 18 (0.08) | 49 (0.22) | 135 (0.60) | 0.27 |
| 2. How I want to be involved | 5.17 (1.23) | 7 (3) | 5 (2) | 7 (0.03) | 31 (0.14) | 46 (0.21) | 127 (0.57) | 0.60 |
| 3. Informing me different options are available | 5.53 (1.12) | 8 (4) | 2 (1) | 4 (0.02) | 8 (0.04) | 29 (0.13) | 172 (0.77) | 0.58 |
| 4. Explaining me advantages and disadvantages | 5.57 (1.00) | 5 (2) | 2 (1) | 3 (0.01) | 12 (0.05) | 31 (0.14) | 170 (0.76) | 0.59 |
| 5. Helping me to understand the information | 5.63 (0.86) | 4 (2) | 0 (0) | 2 (0.01) | 10 (0.04) | 37 (0.17) | 170 (0.76) | 0.54 |
| 6. Asking the treatment option I prefer | 5.07 (1.46) | 12 (5) | 10 (4) | 10 (0.04) | 19 (0.08) | 40 (0.18) | 132 (0.59) | 0.63 |
| 7. Weighing jointly the different options | 5.13 (1.37) | 11 (5) | 8 (4) | 4 (0.02) | 25 (0.11) | 46 (0.21) | 129 (0.58) | 0.66 |
| 8. Selecting a treatment option together | 5.04 (1.41) | 13 (6) | 7 (3) | 6 (0.03) | 28 (0.13) | 48 (0.21) | 121 (0.54) | 0.66 |
| 9. Agreeing on how to proceed | 5.30 (1.23) | 7 (3) | 8 (4) | 5 (0.02) | 10 (0.04) | 53 (0.24) | 140 (0.63) | 0.61 |
The overall scalability (H) is 0.57. Endorsement frequencies: 1 completely disagree; 2 strongly disagree; 3 somewhat disagree; 4 somewhat agree; 5 strongly agree; 6 completely agree