Table 2.
Descriptive statistics of the Patient Health Questionnaire-9 (PHQ-9), status update frequency, and the emotion features expressed in status updates on Facebook (n=29) and Twitter (n=49).
| Variable | |||||||
|
|
Range | Mean (SD) | Median (IQRa) | Range | Mean (SD) | Median (IQR) | |
| Depression severity (PHQ-9b) | 1-22 | 11.48 (6.38) | 10 (5.5-17) | 0-26 | 9.80 (6.81) | 9 (4-14) | |
| Status update frequency |
|
|
|
|
|
|
|
|
|
Recording period (days)c | 22-356 | 170.69 (116.05) | 134 (54-290) | 9-365 | 145.61 (124.97) | 74.00 (33.50-272.00) |
|
|
Status updates per day | 0.03-1.72 | 0.03 (0.36) | 0.16 (0.07-0.51) | 0.03-4.56 | 0.79 (1.09) | 0.40 (0.09-0.90) |
|
|
Interval difference (min) between status updatesd | 661-34827 | 8446.65 (8724.25) | 3818.00 (1877.75-13522.75) | 4.0-28428.5 | 3939.79 (6616.84) | 1037 (206.25-4571.25) |
| Positive emotion words |
|
|
|
|
|
|
|
|
|
Average proportion | 0.02-0.57 | 0.10 (0.10) | 0.08 (0.05-0.11) | 0.01-0.14 | 0.07 (0.03) | 0.08 (0.05-0.09) |
|
|
Variability (iSD)e | 0.04-0.47 | 0.13 (0.09) | 0.10 (0.07-0.16) | 0.03-0.17 | 0.07 (0.03) | 0.08 (0.05-0.09) |
|
|
Instability (time-adjusted MSSD)f | 0.003-11.54 | 1.14 (2.94) | 0.11 (0.02-0.47) | 0.0002-26.80 | 1.49 (4.40) | 0.12 (0.02-0.83) |
| Negative emotion words |
|
|
|
|
|
|
|
|
|
Average proportion | 0.00-0.17 | 0.04 (0.04) | 0.02 (0.01-0.05) | 0.01-0.26 | 0.09 (0.06) | 0.09 (0.04-0.12) |
|
|
Variability (iSDe) | 0.00-0.31 | 0.07 (0.08) | 0.03 (0.02-0.09) | 0.02-0.14 | 0.08 (0.03) | 0.08 (0.06-0.11) |
|
|
Instability (time-adjusted MSSDf) | 0.00-1.23 | 0.11 (0.24) | 0.01 (0.002-0.14) | 0.0006-37.99 | 1.31 (5.43) | 0.15 (0.03-0.49) |
aIQR: interquartile range.
bPHQ-9: Patient Health Questionnaire-9.
cRecording period refers to the range of days between the first status update collected and the administration of the PHQ-9.
dThe median interval differences between status updates.
eiSD refers to within-person variability.
fMSSD: mean squared successive difference.