Table 2.
Asthma symptom study. A DCE with eight choice sets each with two options.
We note that the two levels 0 and 1, should be coded as 1 and −1, respectively, for each attribute when constructing a BFFD.
| Choice Set | Option | Cough | Breathlessness | Wheeze | Chest tightness | Sleep disturbance |
|---|---|---|---|---|---|---|
| 1 | 1 | No cough (0) | Little breathlessness (1) | Some wheezing (1) | A little tightness (1) | No sleep disturbance (0) |
| 2 | Some coughing (1) | No breathlessness (0) | No wheeze (0) | Chest not tight (0) | Awoke once (1) | |
|
| ||||||
| 2 | 1 | No cough (0) | Little breathlessness (1) | Some wheezing (1) | Chest not tight (0) | No sleep disturbance (0) |
| 2 | Some coughing (1) | No breathlessness (0) | No wheeze (0) | A little tightness (1) | Awoke once (1) | |
|
| ||||||
| 3 | 1 | Some coughing (1) | No breathlessness (0) | Some wheezing (1) | Chest not tight (0) | No sleep disturbance (0) |
| 2 | No cough (0) | Little breathlessness (1) | No wheeze (0) | A little tightness (1) | Awoke once (1) | |
|
| ||||||
| 4 | 1 | No cough (0) | Little breathlessness (1) | No wheeze (0) | Chest not tight (0) | Awoke once (1) |
| 2 | Some coughing (1) | No breathlessness (0) | Some wheezing (1) | A little tightness (1) | No sleep disturbance (0) | |
|
| ||||||
| 5 | 1 | No cough (0) | No breathlessness (0) | Some wheezing (1) | A little tightness (1) | Awoke once (1) |
| 2 | Some coughing (1) | Little breathlessness (1) | No wheeze (0) | Chest not tight (0) | No sleep disturbance (0) | |
|
| ||||||
| 6 | 1 | No cough (0) | No breathlessness (0) | Some wheezing (1) | Chest not tight (0) | Awoke once (1) |
| 2 | Some coughing (1) | Little breathlessness (1) | No wheeze (0) | A little tightness (1) | No sleep disturbance (0) | |
|
| ||||||
| 7 | 1 | Some coughing (1) | Little breathlessness (1) | Some wheezing (1) | Chest not tight (0) | Awoke once (1) |
| 2 | No cough (0) | No breathlessness (0) | No wheeze (0) | A little tightness (1) | No sleep disturbance (0) | |
|
| ||||||
| 8 | 1 | Some coughing (1) | Little breathlessness (1) | Some wheezing (1) | A little tightness (1) | Awoke once (1) |
| 2 | No cough (0) | No breathlessness (0) | No wheeze (0) | Chest not tight (0) | No sleep disturbance (0) | |