Table 1.
Patient characteristics
| Covariates | Category | BCS | OBS | Total |
|---|---|---|---|---|
| n = 631 | n = 96 | n = 727 | ||
| Column percent* | ||||
| Age at surgery (year) | < 50 | 15.5 | 25.0 | 16.8 |
| ≥ 50 to < 65 | 56.6 | 52.1 | 56.0 | |
| ≥ 65 | 27.9 | 22.9 | 27.2 | |
| Menopause | Premenopausal | 23.6 | 34.4 | 25.0 |
| Postmenopausal | 73.9 | 63.5 | 72.5 | |
| Bra size | A | 8.7 | 13.5 | 9.4 |
| B | 31.2 | 26.0 | 30.5 | |
| C | 26.1 | 24.0 | 25.9 | |
| D | 18.5 | 16.7 | 18.3 | |
| E | 4.1 | 6.3 | 4.4 | |
| ≥ F | 5.1 | 8.3 | 5.5 | |
| Missing | 6.2 | 5.2 | 6.1 | |
| Chest measurement (cm) | ≤ 82 | 20.9 | 21.9 | 21.0 |
| 83–87 | 20.0 | 25.0 | 20.6 | |
| 88–92 | 13.8 | 15.6 | 14.0 | |
| 93–97 | 8.4 | 7.3 | 8.3 | |
| ≥ 98 | 15.1 | 10.4 | 14.4 | |
| Missing | 21.9 | 19.8 | 21.6 | |
| BMI | < 25 | 36.8 | 41.7 | 37.4 |
| 25.0–29.9 | 35.3 | 39.6 | 35.9 | |
| ≥ 30 | 17.6 | 16.7 | 17.5 | |
| Missing | 10.3 | 2.1 | 9.2 | |
| Ever smoker | Non-smoker | 40.6 | 57.3 | 42.8 |
| Smoker | 53.3 | 42.7 | 53.6 | |
| Smoking at surgery | Non-smoker | 77.7 | 86.5 | 78.8 |
| Smoker | 19.5 | 13.5 | 18.7 | |
| Marital status | Single | 7.9 | 11.5 | 8.4 |
| Married | 68.3 | 69.8 | 68.5 | |
| Separated | 0.6 | 1.0 | 0.7 | |
| Divorced | 9.2 | 10.4 | 9.4 | |
| Widow | 13.3 | 7.3 | 12.5 | |
| Living arrangement | Living alone | 23.6 | 18.8 | 23.0 |
| Cohabiting | 69.6 | 77.1 | 70.6 | |
| Others | 3.2 | 1.0 | 2.9 | |
| Educational level (year) | Primary school | 20.8 | 12.5 | 20.6 |
| Secondary school | 10.0 | 12.5 | 10.3 | |
| Short (2) | 32.3 | 22.9 | 31.1 | |
| Medium (3–4) | 31.9 | 37.5 | 32.6 | |
| Higher (3–6) | 4.3 | 7.3 | 4.7 | |
*Column percent does not always add up to 100% as missing data are only shown if > 5%