Table 3.
Subjective outcome concerning quality of life (n = 45).
| Quality of life (SF-36) | Three months n = 44 |
Six months n = 45 |
Twelve months n = 45 |
Group Differencesa P-value |
Effect sizeb 3 m vs 12 m |
Population normsc SF-36 |
Z scored for comparison 12 m vs population norms |
|---|---|---|---|---|---|---|---|
| Mean score (SD) | |||||||
| Physical Functioning | 76 (13.9) | 84 (12.4) | 87 (12.6) | < 0.001 | 0.8 | 91 (17.3) | -0.2 (0.73) |
| Role Physical | 22 (31.9) | 47 (41.0) | 60 (40.0) | < 0.001 | 1.2 | 87 (28.4) | -1.0 (1.46) |
| Bodily Pain | 60 (23.3) | 70 (20.0) | 72 (23.8) | 0.006 | 0.5 | 77 (25.4) | -0.2 (0.95) |
| General Health | 77 (17.1) | 76 (20.8) | 77 (22.0) | 0.978 | 0.0 | 78 (21.0) | -0.0 (1.01) |
| Vitality | 59 (19.5) | 63 (22.2) | 64 (20.0) | 0.444 | 0.2 | 71 (22.0) | -0.3 (0.92) |
| Social Functioning | 84 (20.7) | 84 (22.4) | 89 (19.2) | 0.120 | 0.2 | 90 (18.6) | -0.1 (1.02) |
| Role Emotional | 54 (44.3) | 67 (42.0) | 71 (38.0) | 0.127 | 0.4 | 89 (25.6) | -0.7 (1.49) |
| Mental Health | 72 (20.4) | 72 (23.3) | 75 (20.7) | 0.592 | 0.1 | 82 (18.1) | -0.4 (1.16) |
aFriedman's test. bEffect size for SF-36 was calculated with mean change in score, three months to follow up after twelve months, divided by standard deviation of the three months score. cPopulation norms were obtained from the Swedish SF-36 database for population norms (n = 8930) and were age and gender matched with individuals (n = 1180). dZ-scores (individual value minus mean value of populations norms divided by SD from the population norms) were calculated for all SF-36 parameters at 12 months. SF-36 (0-100) higher score indicates a better health status 0 (poor health) to 100 (optimal health).