Table 2.
Summary statistics of features.
| Service feature | All, mean (SD) | Free-onlya, mean (SD) | Paida, mean (SD) | All (minimum, maximum) | Free-only (minimum, maximum) | Paid (minimum, maximum) | |
| Physician reputation related | |||||||
|
|
Hospital ranking 2 | 0.02 (0.15) | 0.02 (0.16) | 0.01 (0.12) | 0, 1 | 0, 1 | 0, 1 |
|
|
Physician title 1 | 0.46 (0.5) | 0.43 (0.5) | 0.53 (0.5) | 0, 1 | 0, 1 | 0, 1 |
| Patient related | |||||||
|
|
PriorExam | 0.19 (0.39) | 0.06 (0.24) | 0.47 (0.5) | 0, 1 | 0, 1 | 0, 1 |
|
|
Private | 0.08 (0.27) | 0.07 (0.25) | 0.1 (0.3) | 0, 1 | 0, 1 | 0, 1 |
|
|
Offline connection | 0.71 (0.45) | 0.87 (0.33) | 0.36 (0.48) | 0, 1 | 0, 1 | 0, 1 |
| Service delivery related | |||||||
|
|
Total dialog | 7.44 (6.38) | 6.27 (5.03) | 10.04 (8.06) | 1, 35 | 1, 31 | 1, 35 |
|
|
Response rate | 0.19 (0.16) | 0.18 (0.16) | 0.2 (0.17) | 0, 0.875 | 0, 0.75 | 0, 0.875 |
|
|
Answer frequency | 0.22 (0.33) | 0.24 (0.35) | 0.18 (0.29) | 0, 1.25 | 0, 1 | 0, 1.25 |
|
|
Social return | 0.18 (0.38) | 0.18 (0.38) | 0.18 (0.29) | 0, 1 | 0, 1 | 0, 1 |
| Patient involvement related | |||||||
|
|
Patient posts | 5.79 (5.10) | 5.05 (4.38) | 7.43 (6.10) | 1, 28 | 1, 28 | 1, 28 |
|
|
Question frequency | 1.11 (1.2) | 1.2 (1.24) | 0.92 (1.07) | 0, 5.5 | 0, 5.5 | 0, 5.5 |
aMean differences between free and paid services are all significant (P<.001), except for social return (P=.025).