Table 2.
Multivariate factors associated with failed appointments with the corresponding odds ratios, confidence intervals, and p-values.
| Variable* | OR | 95% CI | p-value |
| Age group | |||
| Up to 20 years | 1 | ||
| 21 to 30 years (x1) | 0.96 | (0.83, 1.11) | 0.575 |
| 31 to 40 years (x2) | 0.93 | (0.81, 1.08) | 0.335 |
| 41 to 50 years (x3) | 0.75 | (0.64, 0.86) | <0.001 |
| 51 to 60 years (x4) | 0.66 | (0.57, 0.77) | <0.001 |
| More than 60 years (x5) | 0.84 | (0.73, 0.97) | 0.019 |
| Race | |||
| Chinese | 1 | ||
| Malay (x6) | 1.48 | (1.31, 1.68) | <0.001 |
| Indian (x7) | 1.61 | (1.42, 1.81) | <0.001 |
| Others (x8) | 1.03 | (0.89, 1.18) | 0.716 |
| Days from scheduling to actual appointment | |||
| Up to 7 days | 1 | ||
| 7 to 21 days (x9) | 1.29 | (1.16, 1.42) | <0.001 |
| More than 21 days (x10) | 2.38 | (2.16, 2.62) | <0.001 |
| Percentage of previous failed appointments | |||
| Up to 20% | 1 | ||
| 21% to 40% (x11) | 0.96 | (0.85, 1.09) | 0.565 |
| 41% to 60% (x12) | 1.21 | (1.07, 1.36) | <0.001 |
| More than 60% (x13) | 1.79 | (1.60, 2.00) | <0.001 |
| No previous appointment (x14) | 4.38 | (3.95, 4.86) | <0.001 |
| Provided cell phone number (x15) | 0.10 | (0.09, 0.11) | <0.001 |
| Approximate distance from TTSH | |||
| <6 km | 1 | ||
| 6 to 14 km (x16) | 1.02 | (0.94, 1.11) | 0.596 |
| >14 km (x17) | 1.14 | (1.04, 1.25) | <0.001 |
| Department | |||
| Surgical | 1 | ||
| Medical (x18) | 0.92 | (0.84, 0.99) | 0.049 |
| ENT (x19) | 1.2 | (1.05, 1.37) | 0.008 |
| Ophthalmology (x20) | 1.13 | (1.02, 1.26) | 0.022 |
| Therapy (x21) | 4.73 | (3.85, 5.82) | <0.001 |
| Others (x22) | 20.22 | (15.34, 26.65) | <0.001 |
* The indicator variables as used in the predicted probability equation in Figure 1 are shown in brackets () next to the respective variables.