| Socio-psychological factors | Group 1 (N = 53) | SD | Group 2 (N = 41) | SD | Group 3 (N = 48) | SD | All (N = 142) | SD |
| External factors | 3.7 | 0.9 | 3.5 | 0.9 | 3.8 | 0.9 | 3.7 | 0.9 |
| Convenience factors | 3.2 | 0.6 | 4.0 | 0.6 | 3.5 | 0.7 | 3.5 | 0.7 |
| Management influences | 3.7 | 0.4 | 3.3 | 0.5 | 3.8 | 0.6 | 3.6 | 0.5 |
| Colleague influences | 4.0 | 0.5 | 2.6 | 0.4 | 4.1 | 0.6 | 3.6 | 0.8 |
| Self-efficacy | 3.0 | 0.7 | 2.5 | 0.9 | 3.8 | 0.9 | 3.0 | 0.9 |